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diff --git a/gfx/thebes/cairo-xlib-utils.h b/gfx/thebes/cairo-xlib-utils.h
new file mode 100644
index 0000000000..0125ff12cb
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+++ b/gfx/thebes/cairo-xlib-utils.h
@@ -0,0 +1,115 @@
+/* -*- 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/. */
+
+#ifndef CAIROXLIBUTILS_H_
+#define CAIROXLIBUTILS_H_
+
+#include "cairo.h"
+#include <X11/Xlib.h>
+
+CAIRO_BEGIN_DECLS
+
+/**
+ * This callback encapsulates Xlib-based rendering. We assume that the
+ * execution of the callback is equivalent to compositing some RGBA image of
+ * size (bounds_width, bounds_height) onto the drawable at offset (offset_x,
+ * offset_y), clipped to the union of the clip_rects if num_rects is greater
+ * than zero. This includes the assumption that the same RGBA image
+ * is composited if you call the callback multiple times with the same closure,
+ * display and visual during a single cairo_draw_with_xlib call.
+ *
+ * @return True on success, False on non-recoverable error
+ */
+typedef cairo_bool_t (*cairo_xlib_drawing_callback)(
+    void* closure, Screen* screen, Drawable drawable, Visual* visual,
+    short offset_x, short offset_y, XRectangle* clip_rects,
+    unsigned int num_rects);
+
+/**
+ * This structure captures the result of the native drawing, in case the
+ * caller may wish to reapply the drawing efficiently later.
+ */
+typedef struct {
+  cairo_surface_t* surface;
+  cairo_bool_t uniform_alpha;
+  cairo_bool_t uniform_color;
+  double alpha;   /* valid only if uniform_alpha is TRUE */
+  double r, g, b; /* valid only if uniform_color is TRUE */
+} cairo_xlib_drawing_result_t;
+
+/**
+ * This type specifies whether the native drawing callback draws all pixels
+ * in its bounds opaquely, independent of the contents of the target drawable,
+ * or whether it leaves pixels transparent/translucent or depends on the
+ * existing contents of the target drawable in some way.
+ */
+typedef enum _cairo_xlib_drawing_opacity {
+  CAIRO_XLIB_DRAWING_OPAQUE,
+  CAIRO_XLIB_DRAWING_TRANSPARENT
+} cairo_xlib_drawing_opacity_t;
+
+/**
+ * This type encodes the capabilities of the native drawing callback.
+ *
+ * If CAIRO_XLIB_DRAWING_SUPPORTS_OFFSET is set, 'offset_x' and 'offset_y'
+ * can be nonzero in the call to the callback; otherwise they will be zero.
+ *
+ * If CAIRO_XLIB_DRAWING_SUPPORTS_CLIP_RECT is set, then 'num_rects' can be
+ * zero or one in the call to the callback. If
+ * CAIRO_XLIB_DRAWING_SUPPORTS_CLIP_LIST is set, then 'num_rects' can be
+ * anything in the call to the callback. Otherwise 'num_rects' will be zero.
+ * Do not set both of these values.
+ *
+ * If CAIRO_XLIB_DRAWING_SUPPORTS_ALTERNATE_SCREEN is set, then 'screen' can
+ * be any screen on any display, otherwise it will be the default screen of
+ * the display passed into cairo_draw_with_xlib.
+ *
+ * If CAIRO_XLIB_DRAWING_SUPPORTS_NONDEFAULT_VISUAL is set, then 'visual' can be
+ * any visual, otherwise it will be equal to
+ * DefaultVisualOfScreen (screen).
+ */
+typedef enum {
+  CAIRO_XLIB_DRAWING_SUPPORTS_OFFSET = 0x01,
+  CAIRO_XLIB_DRAWING_SUPPORTS_CLIP_RECT = 0x02,
+  CAIRO_XLIB_DRAWING_SUPPORTS_CLIP_LIST = 0x04,
+  CAIRO_XLIB_DRAWING_SUPPORTS_ALTERNATE_SCREEN = 0x08,
+  CAIRO_XLIB_DRAWING_SUPPORTS_NONDEFAULT_VISUAL = 0x10
+} cairo_xlib_drawing_support_t;
+
+/**
+ * Draw Xlib output into any cairo context. All cairo transforms and effects
+ * are honored, including the current operator. This is equivalent to a
+ * cairo_set_source_surface and then cairo_paint.
+ * @param cr the context to draw into
+ * @param callback the code to perform Xlib rendering
+ * @param closure associated data
+ * @param dpy an X display to use in case the cairo context has no associated X
+ * display
+ * @param width the width of the putative image drawn by the callback
+ * @param height the height of the putative image drawn by the callback
+ * @param is_opaque set to CAIRO_XLIB_DRAWING_IS_OPAQUE to indicate
+ * that all alpha values of the putative image will be 1.0; the pixels drawn
+ * into the Drawable must not depend on the prior contents of the Drawable in
+ * any way
+ * @param capabilities the capabilities of the callback as described above.
+ * @param result if non-NULL, we *may* fill in the struct with information about
+ * the rendered image. 'surface' may be filled in with a surface representing
+ * the image, similar to the target of 'cr'. If 'uniform_alpha' is True then
+ * every pixel of the image has the same alpha value 'alpha'. If
+ * 'uniform_color' is True then every pixel of the image has the same RGB
+ * color (r, g, b). If the image has uniform color and alpha (or alpha is zero,
+ * in which case the color is always uniform) then we won't bother returning
+ * a surface for it.
+ */
+void cairo_draw_with_xlib(cairo_t* cr, cairo_xlib_drawing_callback callback,
+                          void* closure, Display* dpy, unsigned int width,
+                          unsigned int height,
+                          cairo_xlib_drawing_opacity_t is_opaque,
+                          cairo_xlib_drawing_support_t capabilities,
+                          cairo_xlib_drawing_result_t* result);
+
+CAIRO_END_DECLS
+
+#endif /*CAIROXLIBUTILS_H_*/