Adding upstream version 115.7.0esr.upstream/115.7.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 553 insertions, 0 deletions

diff --git a/gfx/thebes/gfxGDIFont.cpp b/gfx/thebes/gfxGDIFont.cpp
new file mode 100644
index 0000000000..2053b33727
--- /dev/null
+++ b/gfx/thebes/gfxGDIFont.cpp
@@ -0,0 +1,553 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "gfxGDIFont.h"
+
+#include "mozilla/MemoryReporting.h"
+#include "mozilla/Sprintf.h"
+#include "mozilla/WindowsVersion.h"
+
+#include <algorithm>
+#include "gfxWindowsPlatform.h"
+#include "gfxContext.h"
+#include "mozilla/Preferences.h"
+#include "nsUnicodeProperties.h"
+#include "gfxFontConstants.h"
+#include "gfxHarfBuzzShaper.h"
+#include "gfxTextRun.h"
+
+#include "cairo-win32.h"
+
+#define ROUND(x) floor((x) + 0.5)
+
+using namespace mozilla;
+using namespace mozilla::gfx;
+using namespace mozilla::unicode;
+
+gfxGDIFont::gfxGDIFont(GDIFontEntry* aFontEntry, const gfxFontStyle* aFontStyle,
+                       AntialiasOption anAAOption)
+    : gfxFont(nullptr, aFontEntry, aFontStyle, anAAOption),
+      mFont(nullptr),
+      mMetrics(nullptr),
+      mIsBitmap(false),
+      mScriptCache(nullptr) {
+  mNeedsSyntheticBold = aFontStyle->NeedsSyntheticBold(aFontEntry);
+
+  Initialize();
+
+  if (mFont) {
+    mUnscaledFont = aFontEntry->LookupUnscaledFont(mFont);
+  }
+}
+
+gfxGDIFont::~gfxGDIFont() {
+  if (mFont) {
+    ::DeleteObject(mFont);
+  }
+  if (mScriptCache) {
+    ScriptFreeCache(&mScriptCache);
+  }
+  delete mMetrics;
+}
+
+gfxFont* gfxGDIFont::CopyWithAntialiasOption(AntialiasOption anAAOption) const {
+  auto entry = static_cast<GDIFontEntry*>(mFontEntry.get());
+  return new gfxGDIFont(entry, &mStyle, anAAOption);
+}
+
+bool gfxGDIFont::ShapeText(DrawTarget* aDrawTarget, const char16_t* aText,
+                           uint32_t aOffset, uint32_t aLength, Script aScript,
+                           nsAtom* aLanguage, bool aVertical,
+                           RoundingFlags aRounding,
+                           gfxShapedText* aShapedText) {
+  if (!mIsValid) {
+    NS_WARNING("invalid font! expect incorrect text rendering");
+    return false;
+  }
+
+  return gfxFont::ShapeText(aDrawTarget, aText, aOffset, aLength, aScript,
+                            aLanguage, aVertical, aRounding, aShapedText);
+}
+
+already_AddRefed<ScaledFont> gfxGDIFont::GetScaledFont(
+    const TextRunDrawParams& aRunParams) {
+  if (ScaledFont* scaledFont = mAzureScaledFont) {
+    return do_AddRef(scaledFont);
+  }
+
+  LOGFONT lf;
+  GetObject(GetHFONT(), sizeof(LOGFONT), &lf);
+
+  RefPtr<ScaledFont> newScaledFont = Factory::CreateScaledFontForGDIFont(
+      &lf, GetUnscaledFont(), GetAdjustedSize());
+  if (!newScaledFont) {
+    return nullptr;
+  }
+
+  InitializeScaledFont(newScaledFont);
+
+  if (mAzureScaledFont.compareExchange(nullptr, newScaledFont.get())) {
+    Unused << newScaledFont.forget();
+  }
+  ScaledFont* scaledFont = mAzureScaledFont;
+  return do_AddRef(scaledFont);
+}
+
+gfxFont::RunMetrics gfxGDIFont::Measure(const gfxTextRun* aTextRun,
+                                        uint32_t aStart, uint32_t aEnd,
+                                        BoundingBoxType aBoundingBoxType,
+                                        DrawTarget* aRefDrawTarget,
+                                        Spacing* aSpacing,
+                                        gfx::ShapedTextFlags aOrientation) {
+  gfxFont::RunMetrics metrics =
+      gfxFont::Measure(aTextRun, aStart, aEnd, aBoundingBoxType, aRefDrawTarget,
+                       aSpacing, aOrientation);
+
+  // if aBoundingBoxType is LOOSE_INK_EXTENTS
+  // and the underlying cairo font may be antialiased,
+  // we can't trust Windows to have considered all the pixels
+  // so we need to add "padding" to the bounds.
+  // (see bugs 475968, 439831, compare also bug 445087)
+  if (aBoundingBoxType == LOOSE_INK_EXTENTS &&
+      mAntialiasOption != kAntialiasNone && metrics.mBoundingBox.Width() > 0) {
+    metrics.mBoundingBox.MoveByX(-aTextRun->GetAppUnitsPerDevUnit());
+    metrics.mBoundingBox.SetWidth(metrics.mBoundingBox.Width() +
+                                  aTextRun->GetAppUnitsPerDevUnit() * 3);
+  }
+
+  return metrics;
+}
+
+void gfxGDIFont::Initialize() {
+  NS_ASSERTION(!mMetrics, "re-creating metrics? this will leak");
+
+  LOGFONTW logFont;
+
+  if (mAdjustedSize == 0.0) {
+    mAdjustedSize = GetAdjustedSize();
+    if (FontSizeAdjust::Tag(mStyle.sizeAdjustBasis) !=
+        FontSizeAdjust::Tag::None) {
+      if (mStyle.sizeAdjust > 0.0 && mAdjustedSize > 0.0) {
+        // to implement font-size-adjust, we first create the "unadjusted" font
+        FillLogFont(logFont, mAdjustedSize);
+        mFont = ::CreateFontIndirectW(&logFont);
+
+        // initialize its metrics so we can calculate size adjustment
+        Initialize();
+
+        // Unless the font was so small that GDI metrics rounded to zero,
+        // calculate the properly adjusted size, and then proceed
+        // to recreate mFont and recalculate metrics
+        if (mMetrics->emHeight > 0.0) {
+          gfxFloat aspect;
+          switch (FontSizeAdjust::Tag(mStyle.sizeAdjustBasis)) {
+            default:
+              MOZ_ASSERT_UNREACHABLE("unhandled sizeAdjustBasis?");
+              aspect = 0.0;
+              break;
+            case FontSizeAdjust::Tag::ExHeight:
+              aspect = mMetrics->xHeight / mMetrics->emHeight;
+              break;
+            case FontSizeAdjust::Tag::CapHeight:
+              aspect = mMetrics->capHeight / mMetrics->emHeight;
+              break;
+            case FontSizeAdjust::Tag::ChWidth: {
+              gfxFloat advance = GetCharAdvance('0');
+              aspect = advance > 0.0 ? advance / mMetrics->emHeight : 0.5;
+              break;
+            }
+            case FontSizeAdjust::Tag::IcWidth:
+            case FontSizeAdjust::Tag::IcHeight: {
+              bool vertical = FontSizeAdjust::Tag(mStyle.sizeAdjustBasis) ==
+                              FontSizeAdjust::Tag::IcHeight;
+              gfxFloat advance = GetCharAdvance(kWaterIdeograph, vertical);
+              aspect = advance > 0.0 ? advance / mMetrics->emHeight : 1.0;
+              break;
+            }
+          }
+          if (aspect > 0.0) {
+            // If we created a shaper above (to measure glyphs), discard it so
+            // we get a new one for the adjusted scaling.
+            delete mHarfBuzzShaper.exchange(nullptr);
+            mAdjustedSize = mStyle.GetAdjustedSize(aspect);
+          }
+        }
+
+        // delete the temporary font and metrics
+        ::DeleteObject(mFont);
+        mFont = nullptr;
+        delete mMetrics;
+        mMetrics = nullptr;
+      } else {
+        mAdjustedSize = 0.0;
+      }
+    }
+  }
+
+  // (bug 724231) for local user fonts, we don't use GDI's synthetic bold,
+  // as it could lead to a different, incompatible face being used
+  // but instead do our own multi-striking
+  if (mNeedsSyntheticBold && GetFontEntry()->IsLocalUserFont()) {
+    mApplySyntheticBold = true;
+  }
+
+  // this may end up being zero
+  mAdjustedSize = ROUND(mAdjustedSize);
+  FillLogFont(logFont, mAdjustedSize);
+  mFont = ::CreateFontIndirectW(&logFont);
+
+  mMetrics = new gfxFont::Metrics;
+  ::memset(mMetrics, 0, sizeof(*mMetrics));
+
+  if (!mFont) {
+    NS_WARNING("Failed creating GDI font");
+    mIsValid = false;
+    return;
+  }
+
+  AutoDC dc;
+  SetGraphicsMode(dc.GetDC(), GM_ADVANCED);
+  AutoSelectFont selectFont(dc.GetDC(), mFont);
+
+  // Get font metrics if size > 0
+  if (mAdjustedSize > 0.0) {
+    OUTLINETEXTMETRIC oMetrics;
+    TEXTMETRIC& metrics = oMetrics.otmTextMetrics;
+
+    if (0 < GetOutlineTextMetrics(dc.GetDC(), sizeof(oMetrics), &oMetrics)) {
+      mMetrics->strikeoutSize = (double)oMetrics.otmsStrikeoutSize;
+      mMetrics->strikeoutOffset = (double)oMetrics.otmsStrikeoutPosition;
+      mMetrics->underlineSize = (double)oMetrics.otmsUnderscoreSize;
+      mMetrics->underlineOffset = (double)oMetrics.otmsUnderscorePosition;
+
+      const MAT2 kIdentityMatrix = {{0, 1}, {0, 0}, {0, 0}, {0, 1}};
+      GLYPHMETRICS gm;
+      DWORD len = GetGlyphOutlineW(dc.GetDC(), char16_t('x'), GGO_METRICS, &gm,
+                                   0, nullptr, &kIdentityMatrix);
+      if (len == GDI_ERROR || gm.gmptGlyphOrigin.y <= 0) {
+        // 56% of ascent, best guess for true type
+        mMetrics->xHeight =
+            ROUND((double)metrics.tmAscent * DEFAULT_XHEIGHT_FACTOR);
+      } else {
+        mMetrics->xHeight = gm.gmptGlyphOrigin.y;
+      }
+      len = GetGlyphOutlineW(dc.GetDC(), char16_t('H'), GGO_METRICS, &gm, 0,
+                             nullptr, &kIdentityMatrix);
+      if (len == GDI_ERROR || gm.gmptGlyphOrigin.y <= 0) {
+        mMetrics->capHeight = metrics.tmAscent - metrics.tmInternalLeading;
+      } else {
+        mMetrics->capHeight = gm.gmptGlyphOrigin.y;
+      }
+      mMetrics->emHeight = metrics.tmHeight - metrics.tmInternalLeading;
+      gfxFloat typEmHeight =
+          (double)oMetrics.otmAscent - (double)oMetrics.otmDescent;
+      mMetrics->emAscent =
+          ROUND(mMetrics->emHeight * (double)oMetrics.otmAscent / typEmHeight);
+      mMetrics->emDescent = mMetrics->emHeight - mMetrics->emAscent;
+      if (oMetrics.otmEMSquare > 0) {
+        mFUnitsConvFactor = float(mAdjustedSize / oMetrics.otmEMSquare);
+      }
+    } else {
+      // Make a best-effort guess at extended metrics
+      // this is based on general typographic guidelines
+
+      // GetTextMetrics can fail if the font file has been removed
+      // or corrupted recently.
+      BOOL result = GetTextMetrics(dc.GetDC(), &metrics);
+      if (!result) {
+        NS_WARNING("Missing or corrupt font data, fasten your seatbelt");
+        mIsValid = false;
+        memset(mMetrics, 0, sizeof(*mMetrics));
+        return;
+      }
+
+      mMetrics->xHeight =
+          ROUND((float)metrics.tmAscent * DEFAULT_XHEIGHT_FACTOR);
+      mMetrics->strikeoutSize = 1;
+      mMetrics->strikeoutOffset =
+          ROUND(mMetrics->xHeight * 0.5f);  // 50% of xHeight
+      mMetrics->underlineSize = 1;
+      mMetrics->underlineOffset =
+          -ROUND((float)metrics.tmDescent * 0.30f);  // 30% of descent
+      mMetrics->emHeight = metrics.tmHeight - metrics.tmInternalLeading;
+      mMetrics->emAscent = metrics.tmAscent - metrics.tmInternalLeading;
+      mMetrics->emDescent = metrics.tmDescent;
+      mMetrics->capHeight = mMetrics->emAscent;
+    }
+
+    mMetrics->internalLeading = metrics.tmInternalLeading;
+    mMetrics->externalLeading = metrics.tmExternalLeading;
+    mMetrics->maxHeight = metrics.tmHeight;
+    mMetrics->maxAscent = metrics.tmAscent;
+    mMetrics->maxDescent = metrics.tmDescent;
+    mMetrics->maxAdvance = metrics.tmMaxCharWidth;
+    mMetrics->aveCharWidth = std::max<gfxFloat>(1, metrics.tmAveCharWidth);
+    // The font is monospace when TMPF_FIXED_PITCH is *not* set!
+    // See http://msdn2.microsoft.com/en-us/library/ms534202(VS.85).aspx
+    if (!(metrics.tmPitchAndFamily & TMPF_FIXED_PITCH)) {
+      mMetrics->maxAdvance = mMetrics->aveCharWidth;
+    }
+
+    mIsBitmap = !(metrics.tmPitchAndFamily & TMPF_VECTOR);
+
+    // For fonts with USE_TYPO_METRICS set in the fsSelection field,
+    // let the OS/2 sTypo* metrics override the previous values.
+    // (see http://www.microsoft.com/typography/otspec/os2.htm#fss)
+    // Using the equivalent values from oMetrics provides inconsistent
+    // results with CFF fonts, so we instead rely on OS2Table.
+    gfxFontEntry::AutoTable os2Table(mFontEntry,
+                                     TRUETYPE_TAG('O', 'S', '/', '2'));
+    if (os2Table) {
+      uint32_t len;
+      const OS2Table* os2 =
+          reinterpret_cast<const OS2Table*>(hb_blob_get_data(os2Table, &len));
+      if (len >= offsetof(OS2Table, sTypoLineGap) + sizeof(int16_t)) {
+        const uint16_t kUseTypoMetricsMask = 1 << 7;
+        if ((uint16_t(os2->fsSelection) & kUseTypoMetricsMask)) {
+          double ascent = int16_t(os2->sTypoAscender);
+          double descent = int16_t(os2->sTypoDescender);
+          double lineGap = int16_t(os2->sTypoLineGap);
+          mMetrics->maxAscent = ROUND(ascent * mFUnitsConvFactor);
+          mMetrics->maxDescent = -ROUND(descent * mFUnitsConvFactor);
+          mMetrics->maxHeight = mMetrics->maxAscent + mMetrics->maxDescent;
+          mMetrics->internalLeading = mMetrics->maxHeight - mMetrics->emHeight;
+          gfxFloat lineHeight =
+              ROUND((ascent - descent + lineGap) * mFUnitsConvFactor);
+          lineHeight = std::max(lineHeight, mMetrics->maxHeight);
+          mMetrics->externalLeading = lineHeight - mMetrics->maxHeight;
+        }
+      }
+      // although sxHeight and sCapHeight are signed fields, we consider
+      // negative values to be erroneous and just ignore them
+      if (uint16_t(os2->version) >= 2) {
+        // version 2 and later includes the x-height and cap-height fields
+        if (len >= offsetof(OS2Table, sxHeight) + sizeof(int16_t) &&
+            int16_t(os2->sxHeight) > 0) {
+          mMetrics->xHeight = ROUND(int16_t(os2->sxHeight) * mFUnitsConvFactor);
+        }
+        if (len >= offsetof(OS2Table, sCapHeight) + sizeof(int16_t) &&
+            int16_t(os2->sCapHeight) > 0) {
+          mMetrics->capHeight =
+              ROUND(int16_t(os2->sCapHeight) * mFUnitsConvFactor);
+        }
+      }
+    }
+
+    WORD glyph;
+    SIZE size;
+    DWORD ret = GetGlyphIndicesW(dc.GetDC(), L" ", 1, &glyph,
+                                 GGI_MARK_NONEXISTING_GLYPHS);
+    if (ret != GDI_ERROR && glyph != 0xFFFF) {
+      mSpaceGlyph = glyph;
+      // Cache the width of a single space.
+      GetTextExtentPoint32W(dc.GetDC(), L" ", 1, &size);
+      mMetrics->spaceWidth = ROUND(size.cx);
+    } else {
+      mMetrics->spaceWidth = mMetrics->aveCharWidth;
+    }
+
+    // Cache the width of digit zero, if available.
+    ret = GetGlyphIndicesW(dc.GetDC(), L"0", 1, &glyph,
+                           GGI_MARK_NONEXISTING_GLYPHS);
+    if (ret != GDI_ERROR && glyph != 0xFFFF) {
+      GetTextExtentPoint32W(dc.GetDC(), L"0", 1, &size);
+      mMetrics->zeroWidth = ROUND(size.cx);
+    } else {
+      mMetrics->zeroWidth = -1.0;  // indicates not found
+    }
+
+    wchar_t ch = kWaterIdeograph;
+    ret = GetGlyphIndicesW(dc.GetDC(), &ch, 1, &glyph,
+                           GGI_MARK_NONEXISTING_GLYPHS);
+    if (ret != GDI_ERROR && glyph != 0xFFFF) {
+      GetTextExtentPoint32W(dc.GetDC(), &ch, 1, &size);
+      mMetrics->ideographicWidth = ROUND(size.cx);
+    } else {
+      mMetrics->ideographicWidth = -1.0;
+    }
+
+    SanitizeMetrics(mMetrics, GetFontEntry()->mIsBadUnderlineFont);
+  } else {
+    mFUnitsConvFactor = 0.0;  // zero-sized font: all values scale to zero
+  }
+
+  if (ApplySyntheticBold()) {
+    auto delta = GetSyntheticBoldOffset();
+    mMetrics->spaceWidth += delta;
+    mMetrics->aveCharWidth += delta;
+    mMetrics->maxAdvance += delta;
+    if (mMetrics->zeroWidth > 0) {
+      mMetrics->zeroWidth += delta;
+    }
+    if (mMetrics->ideographicWidth > 0) {
+      mMetrics->ideographicWidth += delta;
+    }
+  }
+
+#if 0
+    printf("Font: %p (%s) size: %f adjusted size: %f valid: %s\n", this,
+           GetName().get(), mStyle.size, mAdjustedSize, (mIsValid ? "yes" : "no"));
+    printf("    emHeight: %f emAscent: %f emDescent: %f\n", mMetrics->emHeight, mMetrics->emAscent, mMetrics->emDescent);
+    printf("    maxAscent: %f maxDescent: %f maxAdvance: %f\n", mMetrics->maxAscent, mMetrics->maxDescent, mMetrics->maxAdvance);
+    printf("    internalLeading: %f externalLeading: %f\n", mMetrics->internalLeading, mMetrics->externalLeading);
+    printf("    spaceWidth: %f aveCharWidth: %f\n", mMetrics->spaceWidth, mMetrics->aveCharWidth);
+    printf("    xHeight: %f capHeight: %f\n", mMetrics->xHeight, mMetrics->capHeight);
+    printf("    uOff: %f uSize: %f stOff: %f stSize: %f\n",
+           mMetrics->underlineOffset, mMetrics->underlineSize, mMetrics->strikeoutOffset, mMetrics->strikeoutSize);
+#endif
+}
+
+void gfxGDIFont::FillLogFont(LOGFONTW& aLogFont, gfxFloat aSize) {
+  GDIFontEntry* fe = static_cast<GDIFontEntry*>(GetFontEntry());
+
+  // Figure out the lfWeight value to use for GDI font selection,
+  // or zero to use the entry's current LOGFONT value.
+  LONG weight;
+  if (fe->IsUserFont()) {
+    if (fe->IsLocalUserFont()) {
+      // for local user fonts, don't change the original weight
+      // in the entry's logfont, because that could alter the
+      // choice of actual face used (bug 724231)
+      weight = 0;
+    } else {
+      // avoid GDI synthetic bold which occurs when weight
+      // specified is >= font data weight + 200
+      weight = mNeedsSyntheticBold ? 700 : 200;
+    }
+  } else {
+    // GDI doesn't support variation fonts, so for system fonts we know
+    // that the entry has only a single weight, not a range.
+    MOZ_ASSERT(fe->Weight().IsSingle());
+    weight = mNeedsSyntheticBold ? 700 : fe->Weight().Min().ToIntRounded();
+  }
+
+  fe->FillLogFont(&aLogFont, weight, aSize);
+}
+
+uint32_t gfxGDIFont::GetGlyph(uint32_t aUnicode, uint32_t aVarSelector) {
+  // Callback used only for fonts that lack a 'cmap' table.
+
+  // We don't support variation selector sequences or non-BMP characters
+  // in the legacy bitmap, vector or postscript fonts that might use
+  // this code path.
+  if (aUnicode > 0xffff || aVarSelector) {
+    return 0;
+  }
+
+  if (!mGlyphIDs) {
+    mGlyphIDs = MakeUnique<nsTHashMap<nsUint32HashKey, uint32_t>>(64);
+  }
+
+  uint32_t gid;
+  if (mGlyphIDs->Get(aUnicode, &gid)) {
+    return gid;
+  }
+
+  wchar_t ch = aUnicode;
+  WORD glyph;
+  HRESULT ret = ScriptGetCMap(nullptr, &mScriptCache, &ch, 1, 0, &glyph);
+  if (ret != S_OK) {
+    AutoDC dc;
+    AutoSelectFont fs(dc.GetDC(), GetHFONT());
+    if (ret == E_PENDING) {
+      // Try ScriptGetCMap again now that we've set up the font.
+      ret = ScriptGetCMap(dc.GetDC(), &mScriptCache, &ch, 1, 0, &glyph);
+    }
+    if (ret != S_OK) {
+      // If ScriptGetCMap still failed, fall back to GetGlyphIndicesW
+      // (see bug 1105807).
+      DWORD ret = GetGlyphIndicesW(dc.GetDC(), &ch, 1, &glyph,
+                                   GGI_MARK_NONEXISTING_GLYPHS);
+      if (ret == GDI_ERROR || glyph == 0xFFFF) {
+        glyph = 0;
+      }
+    }
+  }
+
+  mGlyphIDs->InsertOrUpdate(aUnicode, glyph);
+  return glyph;
+}
+
+int32_t gfxGDIFont::GetGlyphWidth(uint16_t aGID) {
+  if (!mGlyphWidths) {
+    mGlyphWidths = MakeUnique<nsTHashMap<nsUint32HashKey, int32_t>>(128);
+  }
+
+  return mGlyphWidths->WithEntryHandle(aGID, [&](auto&& entry) {
+    if (!entry) {
+      DCForMetrics dc;
+      AutoSelectFont fs(dc, GetHFONT());
+
+      int devWidth;
+      if (!GetCharWidthI(dc, aGID, 1, nullptr, &devWidth)) {
+        return -1;
+      }
+      // clamp value to range [0..0x7fff], and convert to 16.16 fixed-point
+      devWidth = std::min(std::max(0, devWidth), 0x7fff);
+      entry.Insert(devWidth << 16);
+    }
+    return *entry;
+  });
+}
+
+bool gfxGDIFont::GetGlyphBounds(uint16_t aGID, gfxRect* aBounds, bool aTight) {
+  DCForMetrics dc;
+  AutoSelectFont fs(dc, GetHFONT());
+
+  if (mIsBitmap) {
+    int devWidth;
+    if (!GetCharWidthI(dc, aGID, 1, nullptr, &devWidth)) {
+      return false;
+    }
+    devWidth = std::min(std::max(0, devWidth), 0x7fff);
+
+    *aBounds = gfxRect(0, -mMetrics->maxAscent, devWidth,
+                       mMetrics->maxAscent + mMetrics->maxDescent);
+    return true;
+  }
+
+  const MAT2 kIdentityMatrix = {{0, 1}, {0, 0}, {0, 0}, {0, 1}};
+  GLYPHMETRICS gm;
+  if (GetGlyphOutlineW(dc, aGID, GGO_METRICS | GGO_GLYPH_INDEX, &gm, 0, nullptr,
+                       &kIdentityMatrix) == GDI_ERROR) {
+    return false;
+  }
+
+  if (gm.gmBlackBoxX == 1 && gm.gmBlackBoxY == 1 &&
+      !GetGlyphOutlineW(dc, aGID, GGO_NATIVE | GGO_GLYPH_INDEX, &gm, 0, nullptr,
+                        &kIdentityMatrix)) {
+    // Workaround for GetGlyphOutline returning 1x1 bounding box
+    // for <space> glyph that is in fact empty.
+    gm.gmBlackBoxX = 0;
+    gm.gmBlackBoxY = 0;
+  } else if (gm.gmBlackBoxX > 0 && !aTight) {
+    // The bounding box reported by Windows supposedly contains the glyph's
+    // "black" area; however, antialiasing (especially with ClearType) means
+    // that the actual image that needs to be rendered may "bleed" into the
+    // adjacent pixels, mainly on the right side.
+    gm.gmptGlyphOrigin.x -= 1;
+    gm.gmBlackBoxX += 3;
+  }
+
+  *aBounds = gfxRect(gm.gmptGlyphOrigin.x, -gm.gmptGlyphOrigin.y,
+                     gm.gmBlackBoxX, gm.gmBlackBoxY);
+  return true;
+}
+
+void gfxGDIFont::AddSizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf,
+                                        FontCacheSizes* aSizes) const {
+  gfxFont::AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
+  aSizes->mFontInstances += aMallocSizeOf(mMetrics);
+  if (mGlyphWidths) {
+    aSizes->mFontInstances +=
+        mGlyphWidths->ShallowSizeOfIncludingThis(aMallocSizeOf);
+  }
+}
+
+void gfxGDIFont::AddSizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf,
+                                        FontCacheSizes* aSizes) const {
+  aSizes->mFontInstances += aMallocSizeOf(this);
+  AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
+}