Track the region where text is painted.

Source/core/platform/graphics/GraphicsContext.cpp

Index: Source/core/platform/graphics/GraphicsContext.cpp
diff --git a/Source/core/platform/graphics/GraphicsContext.cpp b/Source/core/platform/graphics/GraphicsContext.cpp
index 72f98442ebca68df2e0a480d48a6516389aef542..d69df3ac280a279f6e15bce3e4709c35124ae895 100644
--- a/Source/core/platform/graphics/GraphicsContext.cpp
+++ b/Source/core/platform/graphics/GraphicsContext.cpp
@@ -380,23 +380,23 @@ bool GraphicsContext::paintingDisabled() const
     return m_state.paintingDisabled;
 }
 
-void GraphicsContext::drawText(const Font& font, const TextRun& run, const FloatPoint& point, int from, int to)
+void GraphicsContext::drawText(const Font& font, const TextRun& run, const FloatPoint& point, const FloatRect& textRect, int from, int to)
 {
     if (paintingDisabled())
         return;
 
-    font.drawText(this, run, point, from, to);
+    font.drawText(this, run, point, textRect, from, to);
 }
 
-void GraphicsContext::drawEmphasisMarks(const Font& font, const TextRun& run, const AtomicString& mark, const FloatPoint& point, int from, int to)
+void GraphicsContext::drawEmphasisMarks(const Font& font, const TextRun& run, const AtomicString& mark, const FloatPoint& point, const FloatRect& textRect, int from, int to)
 {
     if (paintingDisabled())
         return;
 
-    font.drawEmphasisMarks(this, run, mark, point, from, to);
+    font.drawEmphasisMarks(this, run, mark, point, textRect, from, to);
 }
 
-void GraphicsContext::drawBidiText(const Font& font, const TextRun& run, const FloatPoint& point, Font::CustomFontNotReadyAction customFontNotReadyAction)
+void GraphicsContext::drawBidiText(const Font& font, const TextRun& run, const FloatPoint& point, const FloatRect& textRect, Font::CustomFontNotReadyAction customFontNotReadyAction)
 {
     if (paintingDisabled())
         return;
@@ -420,7 +420,7 @@ void GraphicsContext::drawBidiText(const Font& font, const TextRun& run, const F
         subrun.setDirection(isRTL ? RTL : LTR);
         subrun.setDirectionalOverride(bidiRun->dirOverride(false));
 
-        font.drawText(this, subrun, currPoint, 0, -1, customFontNotReadyAction);
+        font.drawText(this, subrun, currPoint, textRect, 0, -1, customFontNotReadyAction);
 
         bidiRun = bidiRun->next();
         // FIXME: Have Font::drawText return the width of what it drew so that we don't have to re-measure here.