Add CullRect::toString

third_party/WebKit/Source/platform/graphics/paint/CullRect.h

Index: third_party/WebKit/Source/platform/graphics/paint/CullRect.h
diff --git a/third_party/WebKit/Source/platform/graphics/paint/CullRect.h b/third_party/WebKit/Source/platform/graphics/paint/CullRect.h
index 2acc7881ef29ff421ec69bf2117963412795dceb..20ca2ad43f16c4fdd0d91fa15d48ee2d3ce17d92 100644
--- a/third_party/WebKit/Source/platform/graphics/paint/CullRect.h
+++ b/third_party/WebKit/Source/platform/graphics/paint/CullRect.h
@@ -10,6 +10,7 @@
 #include "wtf/Allocator.h"
 #include "wtf/HashMap.h"
 #include "wtf/ListHashSet.h"
+#include "wtf/text/WTFString.h"
 
 #include <limits>
 
@@ -35,6 +36,8 @@ class PLATFORM_EXPORT CullRect {
   bool intersectsHorizontalRange(LayoutUnit lo, LayoutUnit hi) const;
   bool intersectsVerticalRange(LayoutUnit lo, LayoutUnit hi) const;
 
+  String toString() const { return m_rect.toString(); }
+
  private:
   IntRect m_rect;