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

Source/core/paint/ListItemPainter.h

Index: Source/core/paint/ListItemPainter.h
diff --git a/Source/core/paint/ListItemPainter.h b/Source/core/paint/ListItemPainter.h
index d28787b24f2af29c81bf8236c9f8f84140c97dee..adc61556e6feaafde6624ecd90199fe018728e07 100644
--- a/Source/core/paint/ListItemPainter.h
+++ b/Source/core/paint/ListItemPainter.h
@@ -5,6 +5,8 @@
 #ifndef ListItemPainter_h
 #define ListItemPainter_h
 
+#include "wtf/Allocator.h"
+
 namespace blink {
 
 struct PaintInfo;
@@ -13,6 +15,7 @@ class LayoutListItem;
 class LayoutPoint;
 
 class ListItemPainter {
+    STACK_ALLOCATED();
 public:
     ListItemPainter(LayoutListItem& layoutListItem) : m_layoutListItem(layoutListItem) { }