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..7712f144dc7e9d962c8a4a920191f940d49d2264 100644
--- a/content/browser/compositor/browser_compositor_output_surface.cc
+++ b/content/browser/compositor/browser_compositor_output_surface.cc
@@ -10,7 +10,9 @@
 #include "base/command_line.h"
 #include "base/location.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/thread_task_runner_handle.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"
@@ -25,10 +27,13 @@ BrowserCompositorOutputSurface::BrowserCompositorOutputSurface(
         overlay_candidate_validator)
     : OutputSurface(context_provider, worker_context_provider),
       vsync_manager_(vsync_manager),
+      synthetic_begin_frame_source_(new cc::SyntheticBeginFrameSource(
+          base::ThreadTaskRunnerHandle::Get().get(),

[no sievers, 2016/04/05 23:12:52]

Shouldn't it be the same thread that BindToClient() binds to i.e. don't you have
to do it there?
(Even if currently everything might be single-threaded.)

[enne (OOO), 2016/04/06 21:42:58]

Done.

+          cc::BeginFrameArgs::DefaultInterval())),
       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();
 }
@@ -38,10 +43,13 @@ BrowserCompositorOutputSurface::BrowserCompositorOutputSurface(
     const scoped_refptr<ui::CompositorVSyncManager>& vsync_manager)
     : OutputSurface(std::move(software_device)),
       vsync_manager_(vsync_manager),
+      synthetic_begin_frame_source_(new cc::SyntheticBeginFrameSource(
+          base::ThreadTaskRunnerHandle::Get().get(),
+          cc::BeginFrameArgs::DefaultInterval())),
       reflector_(nullptr),
       use_begin_frame_scheduling_(
-          base::CommandLine::ForCurrentProcess()
-              ->HasSwitch(cc::switches::kEnableBeginFrameScheduling)) {
+          base::CommandLine::ForCurrentProcess()->HasSwitch(
+              cc::switches::kEnableBeginFrameScheduling)) {
   Initialize();
 }
 
@@ -67,18 +75,31 @@ 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);
+}
+
 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;
   }