Only Record Ugliness Histogram for Compositor Side Changes

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index 06b3d8db19abb4eb3bb93febd19f0299f5b5cf6b..4422c90c79099f406ee2ffd0bda1bac832108111 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -924,7 +924,7 @@ DrawResult LayerTreeHostImpl::CalculateRenderPasses(
   // If we're making a frame to draw, it better have at least one render pass.
   DCHECK(!frame->render_passes.empty());
 
-  if (IsCurrentlyScrolling()) {
+  if (active_tree_->has_ever_been_drawn()) {
     UMA_HISTOGRAM_COUNTS_100(
         "Compositing.RenderPass.AppendQuadData.NumMissingTiles",
         num_missing_tiles);
@@ -1524,6 +1524,7 @@ void LayerTreeHostImpl::DrawLayers(FrameData* frame,
   }
   active_tree_->root_layer()->ResetAllChangeTrackingForSubtree();
 
+  active_tree_->set_has_ever_been_drawn(true);
   devtools_instrumentation::DidDrawFrame(id_);
   benchmark_instrumentation::IssueImplThreadRenderingStatsEvent(
       rendering_stats_instrumentation_->impl_thread_rendering_stats());