Track the region where text is painted.

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

Index: Source/core/platform/graphics/skia/SkiaFontWin.cpp
diff --git a/Source/core/platform/graphics/skia/SkiaFontWin.cpp b/Source/core/platform/graphics/skia/SkiaFontWin.cpp
index 8a0b7ce2a8ce988e37518d1723762db357469b88..d4971aee692e192bc3a5136881c71f30294b2e99 100644
--- a/Source/core/platform/graphics/skia/SkiaFontWin.cpp
+++ b/Source/core/platform/graphics/skia/SkiaFontWin.cpp
@@ -47,6 +47,7 @@ namespace WebCore {
 
 static void skiaDrawText(PlatformContextSkia* context,
                          const SkPoint& point,
+                         const SkRect& textRect,
                          SkPaint* paint,
                          const WORD* glyphs,
                          const int* advances,
@@ -70,7 +71,7 @@ static void skiaDrawText(PlatformContextSkia* context,
                        y + -SkIntToScalar(offsets[i].dv));
             x += SkIntToScalar(advances[i]);
         }
-        context->drawPosText(glyphs, numGlyphs * sizeof(uint16_t), pos, *paint);
+        context->drawPosText(glyphs, numGlyphs * sizeof(uint16_t), pos, textRect, *paint);
     } else {
         SkAutoSTArray<kLocalGlyphMax * 2, SkScalar> storage(numGlyphs);
         SkScalar* xpos = storage.get();
@@ -79,7 +80,7 @@ static void skiaDrawText(PlatformContextSkia* context,
             x += SkIntToScalar(advances[i]);
         }
         context->drawPosTextH(glyphs, numGlyphs * sizeof(uint16_t),
-                             xpos, y, *paint);
+                             xpos, y, textRect, *paint);
     }
 }
 
@@ -161,7 +162,8 @@ static void paintSkiaText(GraphicsContext* context, HFONT hfont,
                           const WORD* glyphs,
                           const int* advances,
                           const GOFFSET* offsets,
-                          const SkPoint* origin)
+                          const SkPoint& origin,
+                          const SkRect& textRect)
 {
     PlatformContextSkia* platformContext = context->platformContext();
     TextDrawingModeFlags textMode = platformContext->getTextDrawingMode();
@@ -178,7 +180,7 @@ static void paintSkiaText(GraphicsContext* context, HFONT hfont,
     bool didFill = false;
 
     if ((textMode & TextModeFill) && (SkColorGetA(paint.getColor()) || paint.getLooper())) {
-        skiaDrawText(platformContext, *origin, &paint, &glyphs[0], &advances[0], &offsets[0], numGlyphs);
+        skiaDrawText(platformContext, origin, textRect, &paint, &glyphs[0], &advances[0], &offsets[0], numGlyphs);
         didFill = true;
     }
 
@@ -205,7 +207,7 @@ static void paintSkiaText(GraphicsContext* context, HFONT hfont,
             paint.setLooper(0);
         }
 
-        skiaDrawText(platformContext, *origin, &paint, &glyphs[0], &advances[0], &offsets[0], numGlyphs);
+        skiaDrawText(platformContext, origin, textRect, &paint, &glyphs[0], &advances[0], &offsets[0], numGlyphs);
     }
 }
 
@@ -217,10 +219,11 @@ void paintSkiaText(GraphicsContext* context,
                    const WORD* glyphs,
                    const int* advances,
                    const GOFFSET* offsets,
-                   const SkPoint* origin)
+                   const SkPoint& origin,
+                   const SkRect& textRect)
 {
     paintSkiaText(context, data.hfont(), data.typeface(), data.size(), data.lfQuality(),
-                  numGlyphs, glyphs, advances, offsets, origin);
+                  numGlyphs, glyphs, advances, offsets, origin, textRect);
 }
 
 void paintSkiaText(GraphicsContext* context,
@@ -229,14 +232,15 @@ void paintSkiaText(GraphicsContext* context,
                    const WORD* glyphs,
                    const int* advances,
                    const GOFFSET* offsets,
-                   const SkPoint* origin)
+                   const SkPoint& origin,
+                   const SkRect& textRect)
 {
     int size;
     int quality;
     SkTypeface* face = CreateTypefaceFromHFont(hfont, &size, &quality);
     SkAutoUnref aur(face);
 
-    paintSkiaText(context, hfont, face, size, quality, numGlyphs, glyphs, advances, offsets, origin);
+    paintSkiaText(context, hfont, face, size, quality, numGlyphs, glyphs, advances, offsets, origin, textRect);
 }
 
 }  // namespace WebCore