Use HitTestAggregator in GpuRootCompositorFrameSink

components/viz/frame_sinks/gpu_root_compositor_frame_sink.cc

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/viz/frame_sinks/gpu_root_compositor_frame_sink.h"
 
+#include "base/command_line.h"
 #include "cc/surfaces/compositor_frame_sink_support.h"
 #include "cc/surfaces/display.h"
+#include "components/viz/base/switches.h"
+#include "components/viz/hit_test/display_hit_test_data_factory_local.h"
 
 namespace viz {
 
 GpuRootCompositorFrameSink::GpuRootCompositorFrameSink(
     GpuCompositorFrameSinkDelegate* delegate,
     cc::SurfaceManager* surface_manager,
     const cc::FrameSinkId& frame_sink_id,
     std::unique_ptr<cc::Display> display,
     std::unique_ptr<cc::BeginFrameSource> begin_frame_source,
     cc::mojom::MojoCompositorFrameSinkAssociatedRequest request,
@@ skipping 20 matching lines @@
   DCHECK(display_begin_frame_source_);
   compositor_frame_sink_binding_.set_connection_error_handler(
       base::Bind(&GpuRootCompositorFrameSink::OnClientConnectionLost,
                  base::Unretained(this)));
   compositor_frame_sink_private_binding_.set_connection_error_handler(
       base::Bind(&GpuRootCompositorFrameSink::OnPrivateConnectionLost,
                  base::Unretained(this)));
   surface_manager->RegisterBeginFrameSource(display_begin_frame_source_.get(),
                                             frame_sink_id);
   display_->Initialize(this, surface_manager);
+
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(

[Fady Samuel, 2017/06/15 15:02:40]

We are about to  introduce a bunch of flags. I suggest we create a
FrameSinkManagerSettings object that is populated prior to creation.

[gklassen, 2017/06/15 19:40:17]

Ok.  Can you send me a pointer to a pattern to follow and I will happily set
this up. 

+          switches::kUseVizHitTest)) {
+    auto display_hit_test_data_factory =
+        base::MakeUnique<hit_test::DisplayHitTestDataFactoryLocal>();
+    hit_test_aggregator_ = base::MakeUnique<hit_test::HitTestAggregator>(
+        std::move(display_hit_test_data_factory));
+  }
 }
 
 GpuRootCompositorFrameSink::~GpuRootCompositorFrameSink() {
   support_->surface_manager()->UnregisterBeginFrameSource(
       display_begin_frame_source_.get());
 }
 
 void GpuRootCompositorFrameSink::SetDisplayVisible(bool visible) {
   DCHECK(display_);
   display_->SetVisible(visible);
@@ skipping 49 matching lines @@
   support_->RequestCopyOfSurface(std::move(request));
 }
 
 void GpuRootCompositorFrameSink::DisplayOutputSurfaceLost() {
   // TODO(staraz): Implement this. Client should hear about context/output
   // surface lost.
 }
 
 void GpuRootCompositorFrameSink::DisplayWillDrawAndSwap(
     bool will_draw_and_swap,
-    const cc::RenderPassList& render_pass) {}
+    const cc::RenderPassList& render_pass) {
+  if (hit_test_aggregator_)
+    hit_test_aggregator_->PostTaskAggregate(display_->CurrentSurfaceId());
+}
 
 void GpuRootCompositorFrameSink::DisplayDidDrawAndSwap() {}
 
 void GpuRootCompositorFrameSink::DidReceiveCompositorFrameAck(
     const cc::ReturnedResourceArray& resources) {
   if (client_)
     client_->DidReceiveCompositorFrameAck(resources);
 }
 
 void GpuRootCompositorFrameSink::OnBeginFrame(const cc::BeginFrameArgs& args) {
+  if (hit_test_aggregator_)
+    hit_test_aggregator_->Swap();
   if (client_)
     client_->OnBeginFrame(args);
 }
 
 void GpuRootCompositorFrameSink::ReclaimResources(
     const cc::ReturnedResourceArray& resources) {
   if (client_)
     client_->ReclaimResources(resources);
 }
 
 void GpuRootCompositorFrameSink::WillDrawSurface(
     const cc::LocalSurfaceId& local_surface_id,
     const gfx::Rect& damage_rect) {}
 
 void GpuRootCompositorFrameSink::OnClientConnectionLost() {
   client_connection_lost_ = true;
   // Request destruction of |this| only if both connections are lost.
   delegate_->OnClientConnectionLost(support_->frame_sink_id(),
                                     private_connection_lost_);
 }
 
 void GpuRootCompositorFrameSink::OnPrivateConnectionLost() {
   private_connection_lost_ = true;
   // Request destruction of |this| only if both connections are lost.
   delegate_->OnPrivateConnectionLost(support_->frame_sink_id(),
                                      client_connection_lost_);
 }
 
 }  // namespace viz