Migrate Telemetry from beginWindowSnapshotPNG to Page.captureScreenshot

content/browser/renderer_host/render_widget_host_impl.cc

Index: content/browser/renderer_host/render_widget_host_impl.cc
diff --git a/content/browser/renderer_host/render_widget_host_impl.cc b/content/browser/renderer_host/render_widget_host_impl.cc
index c715fcac51e35b0b9e381cd686dd1453f7b7ecc8..d6dd169379c26c6012820530a080d9e1e0f9db13 100644
--- a/content/browser/renderer_host/render_widget_host_impl.cc
+++ b/content/browser/renderer_host/render_widget_host_impl.cc
@@ -209,7 +209,8 @@ RenderWidgetHostImpl::RenderWidgetHostImpl(RenderWidgetHostDelegate* delegate,
       allow_privileged_mouse_lock_(false),
       has_touch_handler_(false),
       weak_factory_(this),
-      last_input_number_(static_cast<int64>(GetProcess()->GetID()) << 32) {
+      last_input_number_(static_cast<int64>(GetProcess()->GetID()) << 32),
+      next_window_snapshot_id_(0) {
   CHECK(delegate_);
   if (routing_id_ == MSG_ROUTING_NONE) {
     routing_id_ = process_->GetNextRoutingID();
@@ -2402,8 +2403,16 @@ void RenderWidgetHostImpl::FrameSwapped(const ui::LatencyInfo& latency_info) {
   if (latency_info.FindLatency(ui::WINDOW_SNAPSHOT_FRAME_NUMBER_COMPONENT,
                                GetLatencyComponentId(),
                                &window_snapshot_component)) {
-    WindowSnapshotReachedScreen(
-        static_cast<int>(window_snapshot_component.sequence_number));
+    // While GpuBenchmarking V8 extension coexists with Page.captureScreenshot
+    // they share the same LatencyComponentType. To avoid confusion only one
+    // of the two methods should be used when testing a specific renderer.
+    // TODO(kaznacheev): Remove this method when GpuBenchmarking V8 extension is
+    // retired.
+    int id = static_cast<int>(window_snapshot_component.sequence_number);
+    if (pending_window_snapshots_.count(id))
+      WindowSnapshotReachedScreen(id);
+    else
+      WindowSnapshotReachedScreenUnsafe(id);
   }
 
   ui::LatencyInfo::LatencyComponent rwh_component;
@@ -2442,6 +2451,13 @@ void RenderWidgetHostImpl::DidReceiveRendererFrame() {
   view_->DidReceiveRendererFrame();
 }
 
+void RenderWidgetHostImpl::RequestWindowSnapshot(
+    const WindowSnapshotCallback& callback) {
+  int id = next_window_snapshot_id_++;
+  pending_window_snapshots_.insert(std::make_pair(id, callback));
+  Send(new ViewMsg_ForceRedraw(GetRoutingID(), id));
+}
+
 void RenderWidgetHostImpl::WindowSnapshotAsyncCallback(
     int routing_id,
     int snapshot_id,
@@ -2458,7 +2474,7 @@ void RenderWidgetHostImpl::WindowSnapshotAsyncCallback(
       routing_id, snapshot_id, snapshot_size, png_data->data()));
 }
 
-void RenderWidgetHostImpl::WindowSnapshotReachedScreen(int snapshot_id) {
+void RenderWidgetHostImpl::WindowSnapshotReachedScreenUnsafe(int snapshot_id) {
   DCHECK(base::MessageLoopForUI::IsCurrent());
 
   std::vector<unsigned char> png;
@@ -2494,6 +2510,53 @@ void RenderWidgetHostImpl::WindowSnapshotReachedScreen(int snapshot_id) {
                  snapshot_size));
 }
 
+void RenderWidgetHostImpl::WindowSnapshotReachedScreen(int snapshot_id) {
+  DCHECK(base::MessageLoopForUI::IsCurrent());
+
+  gfx::Rect view_bounds = GetView()->GetViewBounds();
+  gfx::Rect snapshot_bounds(view_bounds.size());
+
+  std::vector<unsigned char> png;
+  if (ui::GrabViewSnapshot(
+          GetView()->GetNativeView(), &png, snapshot_bounds)) {
+    OnSnapshotDataReceived(snapshot_id, &png.front(), png.size());
+    return;
+  }
+
+  ui::GrabViewSnapshotAsync(
+      GetView()->GetNativeView(),
+      snapshot_bounds,
+      base::ThreadTaskRunnerHandle::Get(),
+      base::Bind(&RenderWidgetHostImpl::OnSnapshotDataReceivedAsync,
+                 weak_factory_.GetWeakPtr(),
+                 snapshot_id));
+}
+
+void RenderWidgetHostImpl::OnSnapshotDataReceived(int snapshot_id,
+                                                  const unsigned char* data,
+                                                  size_t size) {
+  // Any pending snapshots with a lower ID than the one received are considered
+  // to be implicitly complete, and returned the same snapshot data.
+  PendingSnapshotMap::iterator it = pending_window_snapshots_.begin();
+  while(it != pending_window_snapshots_.end()) {
+      if (it->first <= snapshot_id) {
+        it->second.Run(data, size);
+        pending_window_snapshots_.erase(it++);
+      } else {
+        ++it;
+      }
+  }
+}
+
+void RenderWidgetHostImpl::OnSnapshotDataReceivedAsync(
+    int snapshot_id,
+    scoped_refptr<base::RefCountedBytes> png_data) {
+  if (png_data)
+    OnSnapshotDataReceived(snapshot_id, png_data->front(), png_data->size());
+  else
+    OnSnapshotDataReceived(snapshot_id, NULL, 0);
+}
+
 // static
 void RenderWidgetHostImpl::CompositorFrameDrawn(
     const std::vector<ui::LatencyInfo>& latency_info) {