Hook up ui::Compositor to Display's BeginFrameSource

content/browser/compositor/browser_compositor_output_surface.cc

Index: content/browser/compositor/browser_compositor_output_surface.cc
diff --git a/content/browser/compositor/browser_compositor_output_surface.cc b/content/browser/compositor/browser_compositor_output_surface.cc
index f865702effe067a645bc434c72882385ed5195a5..b37f14ffd7249212deab6b7dbb308d7b5141c59e 100644
--- a/content/browser/compositor/browser_compositor_output_surface.cc
+++ b/content/browser/compositor/browser_compositor_output_surface.cc
@@ -11,6 +11,7 @@
 #include "base/location.h"
 #include "base/strings/string_number_conversions.h"
 #include "cc/base/switches.h"
+#include "cc/output/output_surface_client.h"
 #include "content/browser/compositor/browser_compositor_overlay_candidate_validator.h"
 #include "content/browser/compositor/reflector_impl.h"
 #include "content/common/gpu/client/context_provider_command_buffer.h"
@@ -21,27 +22,31 @@ BrowserCompositorOutputSurface::BrowserCompositorOutputSurface(
     const scoped_refptr<cc::ContextProvider>& context_provider,
     const scoped_refptr<cc::ContextProvider>& worker_context_provider,
     const scoped_refptr<ui::CompositorVSyncManager>& vsync_manager,
+    scoped_ptr<cc::SyntheticBeginFrameSource> synthetic_begin_frame_source,

[sunnyps, 2016/03/28 23:09:48]

BrowserCompositorOutputSurface can create and own the synthetic BFS instead of
it being passed in.

[enne (OOO), 2016/03/29 20:39:52]

It was passed in because creating a BFS required a task runner.

[enne (OOO), 2016/03/30 17:34:41]

Would you rather I just pass in a task runner?

[sunnyps, 2016/03/30 18:56:02]

I think either way is fine. Don't have a strong opinion on it.

     scoped_ptr<BrowserCompositorOverlayCandidateValidator>
         overlay_candidate_validator)
     : OutputSurface(context_provider, worker_context_provider),
       vsync_manager_(vsync_manager),
+      synthetic_begin_frame_source_(std::move(synthetic_begin_frame_source)),
       reflector_(nullptr),
       use_begin_frame_scheduling_(
-          base::CommandLine::ForCurrentProcess()
-              ->HasSwitch(cc::switches::kEnableBeginFrameScheduling)) {
+          base::CommandLine::ForCurrentProcess()->HasSwitch(
+              cc::switches::kEnableBeginFrameScheduling)) {
   overlay_candidate_validator_ = std::move(overlay_candidate_validator);
   Initialize();
 }
 
 BrowserCompositorOutputSurface::BrowserCompositorOutputSurface(
     scoped_ptr<cc::SoftwareOutputDevice> software_device,
-    const scoped_refptr<ui::CompositorVSyncManager>& vsync_manager)
+    const scoped_refptr<ui::CompositorVSyncManager>& vsync_manager,
+    scoped_ptr<cc::SyntheticBeginFrameSource> synthetic_begin_frame_source)
     : OutputSurface(std::move(software_device)),
       vsync_manager_(vsync_manager),
+      synthetic_begin_frame_source_(std::move(synthetic_begin_frame_source)),
       reflector_(nullptr),
       use_begin_frame_scheduling_(
-          base::CommandLine::ForCurrentProcess()
-              ->HasSwitch(cc::switches::kEnableBeginFrameScheduling)) {
+          base::CommandLine::ForCurrentProcess()->HasSwitch(
+              cc::switches::kEnableBeginFrameScheduling)) {
   Initialize();
 }
 
@@ -67,18 +72,34 @@ bool BrowserCompositorOutputSurface::BindToClient(
   if (!OutputSurface::BindToClient(client))
     return false;
 
+  // Pass begin frame source up to Display to use for DisplayScheduler.
+  client->SetBeginFrameSource(synthetic_begin_frame_source_.get());
+
   // Don't want vsync notifications until there is a client.
   if (!use_begin_frame_scheduling_)
     vsync_manager_->AddObserver(this);
   return true;
 }
 
+void BrowserCompositorOutputSurface::UpdateVSyncParametersInternal(
+    base::TimeTicks timebase,
+    base::TimeDelta interval) {
+  if (interval == base::TimeDelta()) {
+    // TODO(brianderson): We should not be receiving 0 intervals.
+    interval = cc::BeginFrameArgs::DefaultInterval();
+  }
+  synthetic_begin_frame_source_->OnUpdateVSyncParameters(timebase, interval);
+
+  // TODO(enne): remove this once vsyncs are no longer used in the renderer.
+  CommitVSyncParameters(timebase, interval);
+}
+
 void BrowserCompositorOutputSurface::OnUpdateVSyncParameters(
     base::TimeTicks timebase,
     base::TimeDelta interval) {
   DCHECK(HasClient());
   DCHECK(!use_begin_frame_scheduling_);
-  CommitVSyncParameters(timebase, interval);
+  UpdateVSyncParametersInternal(timebase, interval);
 }
 
 void BrowserCompositorOutputSurface::OnUpdateVSyncParametersFromGpu(
@@ -86,7 +107,7 @@ void BrowserCompositorOutputSurface::OnUpdateVSyncParametersFromGpu(
     base::TimeDelta interval) {
   DCHECK(HasClient());
   if (use_begin_frame_scheduling_) {
-    CommitVSyncParameters(timebase, interval);
+    UpdateVSyncParametersInternal(timebase, interval);
     return;
   }