Add histograms for animated image types

third_party/WebKit/Source/platform/graphics/BitmapImageMetrics.h

Index: third_party/WebKit/Source/platform/graphics/BitmapImageMetrics.h
diff --git a/third_party/WebKit/Source/platform/graphics/BitmapImageMetrics.h b/third_party/WebKit/Source/platform/graphics/BitmapImageMetrics.h
index 79fe54912806cafdcdd10b9c2802123fc9cb7c0c..bb39a843779bc348d1a3673fc337518ad0636f35 100644
--- a/third_party/WebKit/Source/platform/graphics/BitmapImageMetrics.h
+++ b/third_party/WebKit/Source/platform/graphics/BitmapImageMetrics.h
@@ -30,6 +30,15 @@ class PLATFORM_EXPORT BitmapImageMetrics {
     DecodedImageTypeEnumEnd = ImageBMP + 1
   };
 
+  // Values synced with 'AnimatedImageType' in
+  // src/tools/metrics/histograms/histograms.xml
+  enum AnimatedImageType {
+    AnimatedGIF = 0,
+    AnimatedWEBP = 1,
+    AnimatedPNG = 2,
+    AnimatedImageTypeEnumEnd = AnimatedPNG + 1
+  };
+
   enum Gamma {
     // Values synced with 'Gamma' in src/tools/metrics/histograms/histograms.xml
     GammaLinear = 0,
@@ -47,6 +56,7 @@ class PLATFORM_EXPORT BitmapImageMetrics {
   };
 
   static void countDecodedImageType(const String& type);
+  static void countAnimatedImageType(AnimatedImageType);
   static void countImageOrientation(const ImageOrientationEnum);
   static void countImageGammaAndGamut(SkColorSpace*);
   static void countOutputGammaAndGamut(SkColorSpace*);