Add fixed raster scale use counter histograms.

third_party/WebKit/Source/platform/testing/WebLayerTreeViewImplForTesting.h

Index: third_party/WebKit/Source/platform/testing/WebLayerTreeViewImplForTesting.h
diff --git a/third_party/WebKit/Source/platform/testing/WebLayerTreeViewImplForTesting.h b/third_party/WebKit/Source/platform/testing/WebLayerTreeViewImplForTesting.h
index a4e3d2a50dfcc6bd610d9eca953997b3ef8f96ca..39f943afcd63b557b62c95ee5e456089ef1da96d 100644
--- a/third_party/WebKit/Source/platform/testing/WebLayerTreeViewImplForTesting.h
+++ b/third_party/WebKit/Source/platform/testing/WebLayerTreeViewImplForTesting.h
@@ -93,6 +93,9 @@ public:
     void DidCommitAndDrawFrame() override {}
     void DidCompleteSwapBuffers() override {}
     void DidCompletePageScaleAnimation() override {}
+    void ReportFixedRasterScaleUseCounters(
+        bool hasBlurryContent,
+        bool hasPotentialPerformanceRegression) override {}
 
     // cc::LayerTreeHostSingleThreadClient implementation.
     void DidPostSwapBuffers() override {}