Add display list fallback reason histograms for 2D canvas

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

Index: third_party/WebKit/Source/platform/graphics/GraphicsTypes.h
diff --git a/third_party/WebKit/Source/platform/graphics/GraphicsTypes.h b/third_party/WebKit/Source/platform/graphics/GraphicsTypes.h
index 4f73466c314b24fa0cfd84bd8c1c1f2020085e08..7af6fb346143c14f912edc39f89a6184a1b7268b 100644
--- a/third_party/WebKit/Source/platform/graphics/GraphicsTypes.h
+++ b/third_party/WebKit/Source/platform/graphics/GraphicsTypes.h
@@ -84,6 +84,34 @@ enum AccelerationHint {
     PreferNoAcceleration,
 };
 
+enum SnapshotReason {
+    SnapshotReasonUnknown,
+    SnapshotReasonGetImageData,
+    SnapshotReasonCopyToWebGLTexture,
+    SnapshotReasonPaint,
+    SnapshotReasonToDataURL,
+    SnapshotReasonToBlob,
+    SnapshotReasonCanvasListenerCapture,
+    SnapshotReasonDrawImage,
+    SnapshotReasonCreatePattern,
+};
+
+// Note: enum used directly for histogram, values must not change
+enum DisableDeferralReason {
+    DisableDeferralReasonUnknown = 0, // Should not appear in production histograms
+    DisableDeferralReasonExpensiveOverdrawHeuristic = 1,
+    DisableDeferralReasonUsingTextureBackedPattern = 2,
+    DisableDeferralReasonDrawImageOfVideo = 3,
+    DisableDeferralReasonDrawImageOfAnimated2dCanvas = 4,
+    DisableDeferralReasonCount,
+};
+
+enum FlushReason {
+    FlushReasonUnknown,
+    FlushReasonInitialClear,
+    FlushReasonDrawImageOfWebGL,
+};
+
 enum ImageInitializationMode {
     InitializeImagePixels,
     DoNotInitializeImagePixels,