1 files changed, 132 insertions, 0 deletions
diff --git a/layout/style/ComputedStyleInlines.h b/layout/style/ComputedStyleInlines.h
new file mode 100644
index 0000000000..f9e87c808f
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+++ b/layout/style/ComputedStyleInlines.h
@@ -0,0 +1,132 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+/*
+ * Inlined methods for ComputedStyle. Will just redirect to
+ * GeckoComputedStyle methods when compiled without stylo, but will do
+ * virtual dispatch (by checking which kind of container it is)
+ * in stylo mode.
+ */
+
+#ifndef ComputedStyleInlines_h
+#define ComputedStyleInlines_h
+
+#include "mozilla/ComputedStyle.h"
+
+#include "MainThreadUtils.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/Unused.h"
+#include "nsStyleStructInlines.h"
+
+namespace mozilla {
+
+namespace detail {
+
+template <typename T, typename Enable = void>
+struct HasTriggerImageLoads : public std::false_type {};
+
+template <typename T>
+struct HasTriggerImageLoads<T, decltype(std::declval<T&>().TriggerImageLoads(
+                                   std::declval<dom::Document&>(), nullptr))>
+    : public std::true_type {};
+
+template <typename T, const T* (ComputedStyle::*Method)() const>
+void TriggerImageLoads(dom::Document& aDocument, const ComputedStyle* aOldStyle,
+                       ComputedStyle* aStyle) {
+  if constexpr (HasTriggerImageLoads<T>::value) {
+    auto* old = aOldStyle ? (aOldStyle->*Method)() : nullptr;
+    auto* current = const_cast<T*>((aStyle->*Method)());
+    current->TriggerImageLoads(aDocument, old);
+  } else {
+    Unused << aOldStyle;
+    Unused << aStyle;
+  }
+}
+
+}  // namespace detail
+
+void ComputedStyle::StartImageLoads(dom::Document& aDocument,
+                                    const ComputedStyle* aOldStyle) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+#define STYLE_STRUCT(name_)                                                \
+  detail::TriggerImageLoads<nsStyle##name_, &ComputedStyle::Style##name_>( \
+      aDocument, aOldStyle, this);
+#include "nsStyleStructList.h"
+#undef STYLE_STRUCT
+}
+
+StylePointerEvents ComputedStyle::PointerEvents() const {
+  if (IsRootElementStyle()) {
+    // The root frame is not allowed to have pointer-events: none, or else no
+    // frames could be hit test against and scrolling the viewport would not
+    // work.
+    return StylePointerEvents::Auto;
+  }
+  const auto& ui = *StyleUI();
+  if (ui.IsInert()) {
+    return StylePointerEvents::None;
+  }
+  return ui.ComputedPointerEvents();
+}
+
+StyleUserSelect ComputedStyle::UserSelect() const {
+  return StyleUI()->IsInert() ? StyleUserSelect::None
+                              : StyleUIReset()->ComputedUserSelect();
+}
+
+bool ComputedStyle::IsFixedPosContainingBlockForNonSVGTextFrames() const {
+  // NOTE: Any CSS properties that influence the output of this function
+  // should return FIXPOS_CB_NON_SVG for will-change.
+  if (IsRootElementStyle()) {
+    return false;
+  }
+
+  const auto& disp = *StyleDisplay();
+  if (disp.mWillChange.bits & mozilla::StyleWillChangeBits::FIXPOS_CB_NON_SVG) {
+    return true;
+  }
+
+  const auto& effects = *StyleEffects();
+  return effects.HasFilters() || effects.HasBackdropFilters();
+}
+
+bool ComputedStyle::IsFixedPosContainingBlock(
+    const nsIFrame* aContextFrame) const {
+  // NOTE: Any CSS properties that influence the output of this function
+  // should also handle will-change appropriately.
+  if (aContextFrame->IsInSVGTextSubtree()) {
+    return false;
+  }
+  if (IsFixedPosContainingBlockForNonSVGTextFrames()) {
+    return true;
+  }
+  const auto& disp = *StyleDisplay();
+  if (disp.IsFixedPosContainingBlockForContainLayoutAndPaintSupportingFrames() &&
+      aContextFrame->SupportsContainLayoutAndPaint()) {
+    return true;
+  }
+  if (disp.IsFixedPosContainingBlockForTransformSupportingFrames() &&
+      aContextFrame->SupportsCSSTransforms()) {
+    return true;
+  }
+  return false;
+}
+
+bool ComputedStyle::IsAbsPosContainingBlock(
+    const nsIFrame* aContextFrame) const {
+  if (IsFixedPosContainingBlock(aContextFrame)) {
+    return true;
+  }
+  // NOTE: Any CSS properties that influence the output of this function
+  // should also handle will-change appropriately.
+  return StyleDisplay()->IsPositionedStyle() &&
+         !aContextFrame->IsInSVGTextSubtree();
+}
+
+}  // namespace mozilla
+
+#endif  // ComputedStyleInlines_h