cc: Add UMA for tracking decode duration for out of raster decodes.

cc/raster/image_hijack_canvas_unittest.cc

Index: cc/raster/image_hijack_canvas_unittest.cc
diff --git a/cc/raster/image_hijack_canvas_unittest.cc b/cc/raster/image_hijack_canvas_unittest.cc
index 8a9f4affdc3ed3649ca3224b40a871b5654a7576..ebd4d4338dc9390efcef0db08e37f6667bb05e5c 100644
--- a/cc/raster/image_hijack_canvas_unittest.cc
+++ b/cc/raster/image_hijack_canvas_unittest.cc
@@ -30,8 +30,10 @@ class MockImageDecodeCache : public ImageDecodeCache {
   MOCK_METHOD1(SetShouldAggressivelyFreeResources,
                void(bool aggressively_free_resources));
   MOCK_METHOD0(ClearCache, void());
-  MOCK_METHOD2(GetOutOfRasterDecodeTaskForImageAndRef,
-               bool(const DrawImage& image, scoped_refptr<TileTask>* task));
+  MOCK_METHOD3(GetOutOfRasterDecodeTaskForImageAndRef,
+               bool(const DrawImage& image,
+                    ImageDecodeType decode_type,
+                    scoped_refptr<TileTask>* task));
   MOCK_CONST_METHOD0(GetMaximumMemoryLimitBytes, size_t());
 };