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 73c306d28292d3d19feb1d8aec5d5d9ba7fa3633..d4c2c7bb516d06c42f24217e59c2769009b139c3 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_browser_snapshot_id_(0) {
   CHECK(delegate_);
   if (routing_id_ == MSG_ROUTING_NONE) {
     routing_id_ = process_->GetNextRoutingID();
@@ -1225,6 +1226,13 @@ void RenderWidgetHostImpl::GetSnapshotFromRenderer(
   Send(new ViewMsg_Snapshot(GetRoutingID(), copy_rect_in_pixel));
 }
 
+void RenderWidgetHostImpl::GetSnapshotFromBrowser(
+    const base::Callback<void(const unsigned char*,size_t)> callback) {
+  int id = next_browser_snapshot_id_++;
+  pending_browser_snapshots_.insert(std::make_pair(id, callback));
+  Send(new ViewMsg_ForceRedraw(GetRoutingID(), id));
+}
+
 void RenderWidgetHostImpl::OnSnapshot(bool success,
                                     const SkBitmap& bitmap) {
   if (pending_snapshots_.size() == 0) {
@@ -2387,8 +2395,16 @@ 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.

[Ken Russell (switch to Gerrit), 2014/03/11 18:22:29]

That's a non-intuitive restriction that leaves the code in a weird state until
the old GPU benchmarking extension entry point is removed.

[Vladislav Kaznacheev, 2014/03/12 09:24:24]

Fair enough. I will try and remove the old GPU benchmarking extension.

On 2014/03/11 18:22:29, Ken Russell wrote:

+    // TODO(kaznacheev): Remove this method when GpuBenchmarking V8 extension is
+    // retired.
+    int id = static_cast<int>(window_snapshot_component.sequence_number);
+    if (pending_browser_snapshots_.count(id))
+      WindowSnapshotReachedScreen(id);
+    else
+      WindowSnapshotReachedScreenUnsafe(id);
   }
 
   ui::LatencyInfo::LatencyComponent rwh_component;
@@ -2443,7 +2459,7 @@ 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;
@@ -2479,6 +2495,53 @@ 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_browser_snapshots_.begin();
+  while(it != pending_browser_snapshots_.end()) {
+      if (it->first <= snapshot_id) {
+        it->second.Run(data, size);
+        pending_browser_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) {