Make classes and structures in core/paint fast-allocated.

Source/core/paint/SVGTextPainter.h

Index: Source/core/paint/SVGTextPainter.h
diff --git a/Source/core/paint/SVGTextPainter.h b/Source/core/paint/SVGTextPainter.h
index 43f86ed2394dd39eeaa968307de34777617cf4ac..74ee064d1ba23ebef317da6f72b4184ea7cc17cf 100644
--- a/Source/core/paint/SVGTextPainter.h
+++ b/Source/core/paint/SVGTextPainter.h
@@ -5,12 +5,15 @@
 #ifndef SVGTextPainter_h
 #define SVGTextPainter_h
 
+#include "wtf/Allocator.h"
+
 namespace blink {
 
 struct PaintInfo;
 class LayoutSVGText;
 
 class SVGTextPainter {
+    STACK_ALLOCATED();
 public:
     SVGTextPainter(LayoutSVGText& layoutSVGText) : m_layoutSVGText(layoutSVGText) { }
     void paint(const PaintInfo&);