Track the region where text is painted.

Source/core/platform/graphics/skia/SkiaFontWin.h

Index: Source/core/platform/graphics/skia/SkiaFontWin.h
diff --git a/Source/core/platform/graphics/skia/SkiaFontWin.h b/Source/core/platform/graphics/skia/SkiaFontWin.h
index c70f84e6efd0708fb9c9579866631bba64384c5e..b4862d6b77c7d8acdfeb25118159af11fa1c9ed7 100644
--- a/Source/core/platform/graphics/skia/SkiaFontWin.h
+++ b/Source/core/platform/graphics/skia/SkiaFontWin.h
@@ -35,6 +35,7 @@
 #include <usp10.h>
 
 struct SkPoint;
+struct SkRect;
 
 namespace WebCore {
 
@@ -50,7 +51,8 @@ void paintSkiaText(GraphicsContext*,
                    const WORD* glyphs,
                    const int* advances,
                    const GOFFSET* offsets,
-                   const SkPoint* origin);
+                   const SkPoint& origin,
+                   const SkRect& textRect);
 
 // Note that the offsets parameter is optional. If not null it represents a
 // per glyph offset (such as returned by ScriptPlace Windows API function).
@@ -62,7 +64,8 @@ void paintSkiaText(GraphicsContext*,
                    const WORD* glyphs,
                    const int* advances,
                    const GOFFSET* offsets,
-                   const SkPoint* origin);
+                   const SkPoint& origin,
+                   const SkRect& textRect);
 
 }  // namespace WebCore