Add animation support for WebP images

Source/core/page/RuntimeEnabledFeatures.h

Index: Source/core/page/RuntimeEnabledFeatures.h
diff --git a/Source/core/page/RuntimeEnabledFeatures.h b/Source/core/page/RuntimeEnabledFeatures.h
index fc3a4a0dd04c4420180fce1849113c3584488919..8389456a6a7b035f8dee8012ff598d8bbfce2f6f 100644
--- a/Source/core/page/RuntimeEnabledFeatures.h
+++ b/Source/core/page/RuntimeEnabledFeatures.h
@@ -244,6 +244,9 @@ public:
     static bool imeAPIEnabled() { return isIMEAPIEnabled; }
     static void setIMEAPIEnabled(bool isEnabled) { isIMEAPIEnabled = isEnabled; }
 
+    static void setAnimatedWebPEnabled(bool isEnabled) { isAnimatedWebPEnabled = isEnabled; }
+    static bool animatedWebPEnabled() { return isAnimatedWebPEnabled; }
+
 private:
     // Never instantiate.
     RuntimeEnabledFeatures() { }
@@ -326,6 +329,8 @@ private:
     static bool isExperimentalWebSocketEnabled;
 
     static bool isIMEAPIEnabled;
+
+    static bool isAnimatedWebPEnabled;
 };
 
 } // namespace WebCore