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

Source/core/paint/VideoPainter.h

Index: Source/core/paint/VideoPainter.h
diff --git a/Source/core/paint/VideoPainter.h b/Source/core/paint/VideoPainter.h
index 63cbbb4539366608ef115c29fb711a11666f3d31..098e867ce0cb5b6b18fec4276c18c35b19c275d1 100644
--- a/Source/core/paint/VideoPainter.h
+++ b/Source/core/paint/VideoPainter.h
@@ -5,6 +5,8 @@
 #ifndef VideoPainter_h
 #define VideoPainter_h
 
+#include "wtf/Allocator.h"
+
 namespace blink {
 
 struct PaintInfo;
@@ -12,6 +14,7 @@ class LayoutPoint;
 class LayoutVideo;
 
 class VideoPainter {
+    STACK_ALLOCATED();
 public:
     VideoPainter(LayoutVideo& layoutVideo) : m_layoutVideo(layoutVideo) { }