cc: Handle retroactive BeginFrames in the Scheduler.

cc/scheduler/scheduler_unittest.cc

Index: cc/scheduler/scheduler_unittest.cc
diff --git a/cc/scheduler/scheduler_unittest.cc b/cc/scheduler/scheduler_unittest.cc
index 67a064b59d6e93cfefa37f02dc34dfb25edcc217..a8b5b3092306d6452b8ccb805f19ab4fab6dcc9f 100644
--- a/cc/scheduler/scheduler_unittest.cc
+++ b/cc/scheduler/scheduler_unittest.cc
@@ -94,11 +94,15 @@ class FakeSchedulerClient : public SchedulerClient {
   }
 
   // SchedulerClient implementation.
-  virtual void SetNeedsBeginImplFrame(bool enable) OVERRIDE {
-    actions_.push_back("SetNeedsBeginImplFrame");
+  virtual void SetNeedsBeginFrame(bool enable) OVERRIDE {
+    actions_.push_back("SetNeedsBeginFrame");
     states_.push_back(scheduler_->StateAsValue().release());
     needs_begin_impl_frame_ = enable;
   }
+  virtual void WillBeginImplFrame(const BeginFrameArgs& args) OVERRIDE {
+    actions_.push_back("WillBeginImplFrame");
+    states_.push_back(scheduler_->StateAsValue().release());
+  }
   virtual void ScheduledActionSendBeginMainFrame() OVERRIDE {
     actions_.push_back("ScheduledActionSendBeginMainFrame");
     states_.push_back(scheduler_->StateAsValue().release());
@@ -194,7 +198,7 @@ void InitializeOutputSurfaceAndFirstCommit(Scheduler* scheduler,
   scheduler->NotifyBeginMainFrameStarted();
   scheduler->NotifyReadyToCommit();
   // Go through the motions to draw the commit.
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
 
   // Run the posted deadline task.
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
@@ -202,8 +206,8 @@ void InitializeOutputSurfaceAndFirstCommit(Scheduler* scheduler,
   EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
 
   // We need another BeginImplFrame so Scheduler calls
-  // SetNeedsBeginImplFrame(false).
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
+  // SetNeedsBeginFrame(false).
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
 
   // Run the posted deadline task.
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
@@ -240,19 +244,20 @@ TEST(SchedulerTest, RequestCommit) {
   client.Reset();
   scheduler->SetNeedsCommit();
   EXPECT_TRUE(client.needs_begin_impl_frame());
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
   client.Reset();
 
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_SINGLE_ACTION("ScheduledActionSendBeginMainFrame", client);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_ACTION("WillBeginImplFrame", client, 0, 2);
+  EXPECT_ACTION("ScheduledActionSendBeginMainFrame", client, 1, 2);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   EXPECT_TRUE(client.needs_begin_impl_frame());
   client.Reset();
 
   // If we don't swap on the deadline, we need to request another
   // BeginImplFrame.
-  scheduler->OnBeginImplFrameDeadline();
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
   EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
   EXPECT_TRUE(client.needs_begin_impl_frame());
   client.Reset();
@@ -265,29 +270,29 @@ TEST(SchedulerTest, RequestCommit) {
   client.Reset();
 
   // BeginImplFrame should prepare the draw.
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   EXPECT_TRUE(client.needs_begin_impl_frame());
   client.Reset();
 
   // BeginImplFrame deadline should draw.
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_ACTION("ScheduledActionDrawAndSwapIfPossible", client, 0, 2);
-  EXPECT_ACTION("SetNeedsBeginImplFrame", client, 1, 2);
+  EXPECT_ACTION("SetNeedsBeginFrame", client, 1, 2);
   EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
   EXPECT_TRUE(client.needs_begin_impl_frame());
   client.Reset();
 
-  // The following BeginImplFrame deadline should SetNeedsBeginImplFrame(false)
+  // The following BeginImplFrame deadline should SetNeedsBeginFrame(false)
   // to avoid excessive toggles.
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   client.Reset();
 
-  scheduler->OnBeginImplFrameDeadline();
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
   EXPECT_FALSE(client.needs_begin_impl_frame());
   client.Reset();
 }
@@ -306,11 +311,12 @@ TEST(SchedulerTest, RequestCommitAfterBeginMainFrameSent) {
 
   // SetNeedsCommit should begin the frame.
   scheduler->SetNeedsCommit();
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
 
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_SINGLE_ACTION("ScheduledActionSendBeginMainFrame", client);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_ACTION("WillBeginImplFrame", client, 0, 2);
+  EXPECT_ACTION("ScheduledActionSendBeginMainFrame", client, 1, 2);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
 
   EXPECT_TRUE(client.needs_begin_impl_frame());
@@ -327,20 +333,20 @@ TEST(SchedulerTest, RequestCommitAfterBeginMainFrameSent) {
   EXPECT_SINGLE_ACTION("ScheduledActionCommit", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_ACTION("ScheduledActionDrawAndSwapIfPossible", client, 0, 2);
-  EXPECT_ACTION("SetNeedsBeginImplFrame", client, 1, 2);
+  EXPECT_ACTION("SetNeedsBeginFrame", client, 1, 2);
   EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
 
   // Because we just swapped, the Scheduler should also request the next
   // BeginImplFrame from the OutputSurface.
   EXPECT_TRUE(client.needs_begin_impl_frame());
   client.Reset();
-
   // Since another commit is needed, the next BeginImplFrame should initiate
   // the second commit.
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_SINGLE_ACTION("ScheduledActionSendBeginMainFrame", client);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_ACTION("WillBeginImplFrame", client, 0, 2);
+  EXPECT_ACTION("ScheduledActionSendBeginMainFrame", client, 1, 2);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   client.Reset();
 
@@ -351,17 +357,17 @@ TEST(SchedulerTest, RequestCommitAfterBeginMainFrameSent) {
   EXPECT_SINGLE_ACTION("ScheduledActionCommit", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_ACTION("ScheduledActionDrawAndSwapIfPossible", client, 0, 2);
-  EXPECT_ACTION("SetNeedsBeginImplFrame", client, 1, 2);
+  EXPECT_ACTION("SetNeedsBeginFrame", client, 1, 2);
   EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
   EXPECT_TRUE(client.needs_begin_impl_frame());
   client.Reset();
 
   // On the next BeginImplFrame, verify we go back to a quiescent state and
   // no longer request BeginImplFrames.
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_FALSE(client.needs_begin_impl_frame());
   client.Reset();
 }
@@ -379,28 +385,28 @@ TEST(SchedulerTest, TextureAcquisitionCausesCommitInsteadOfDraw) {
   client.Reset();
   scheduler->SetNeedsRedraw();
   EXPECT_TRUE(scheduler->RedrawPending());
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
   EXPECT_TRUE(client.needs_begin_impl_frame());
 
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_ACTION("ScheduledActionDrawAndSwapIfPossible", client, 0, 2);
-  EXPECT_ACTION("SetNeedsBeginImplFrame", client, 1, 2);
+  EXPECT_ACTION("SetNeedsBeginFrame", client, 1, 2);
   EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
   EXPECT_FALSE(scheduler->RedrawPending());
   EXPECT_TRUE(client.needs_begin_impl_frame());
 
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
   EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
   EXPECT_FALSE(scheduler->RedrawPending());
   EXPECT_FALSE(client.needs_begin_impl_frame());
@@ -414,17 +420,17 @@ TEST(SchedulerTest, TextureAcquisitionCausesCommitInsteadOfDraw) {
   client.Reset();
   scheduler->SetNeedsRedraw();
   EXPECT_TRUE(scheduler->RedrawPending());
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
   EXPECT_TRUE(client.needs_begin_impl_frame());
 
   // No draw happens since the textures are acquired by the main thread.
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
   EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
   EXPECT_TRUE(scheduler->RedrawPending());
   EXPECT_TRUE(client.needs_begin_impl_frame());
@@ -434,8 +440,9 @@ TEST(SchedulerTest, TextureAcquisitionCausesCommitInsteadOfDraw) {
   EXPECT_EQ(0, client.num_actions_());
 
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_SINGLE_ACTION("ScheduledActionSendBeginMainFrame", client);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_ACTION("WillBeginImplFrame", client, 0, 2);
+  EXPECT_ACTION("ScheduledActionSendBeginMainFrame", client, 1, 2);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
 
   // Commit will release the texture.
@@ -448,21 +455,21 @@ TEST(SchedulerTest, TextureAcquisitionCausesCommitInsteadOfDraw) {
 
   // Now we can draw again after the commit happens.
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_ACTION("ScheduledActionDrawAndSwapIfPossible", client, 0, 2);
-  EXPECT_ACTION("SetNeedsBeginImplFrame", client, 1, 2);
+  EXPECT_ACTION("SetNeedsBeginFrame", client, 1, 2);
   EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
   EXPECT_FALSE(scheduler->RedrawPending());
   EXPECT_TRUE(client.needs_begin_impl_frame());
 
   // Make sure we stop requesting BeginImplFrames if we don't swap.
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
   EXPECT_FALSE(client.needs_begin_impl_frame());
 }
 
@@ -479,7 +486,7 @@ TEST(SchedulerTest, TextureAcquisitionCollision) {
 
   client.Reset();
   scheduler->SetNeedsCommit();
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
 
   client.Reset();
   scheduler->SetMainThreadNeedsLayerTextures();
@@ -487,16 +494,17 @@ TEST(SchedulerTest, TextureAcquisitionCollision) {
       "ScheduledActionAcquireLayerTexturesForMainThread", client);
 
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_SINGLE_ACTION("ScheduledActionSendBeginMainFrame", client);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_ACTION("WillBeginImplFrame", client, 0, 2);
+  EXPECT_ACTION("ScheduledActionSendBeginMainFrame", client, 1, 2);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
 
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
 
   // Although the compositor cannot draw because textures are locked by main
-  // thread, we continue requesting SetNeedsBeginImplFrame in anticipation of
+  // thread, we continue requesting SetNeedsBeginFrame in anticipation of
   // the unlock.
   EXPECT_TRUE(client.needs_begin_impl_frame());
 
@@ -513,28 +521,28 @@ TEST(SchedulerTest, TextureAcquisitionCollision) {
 
   // No implicit commit is expected.
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
 
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_ACTION("ScheduledActionDrawAndSwapIfPossible", client, 0, 3);
   EXPECT_ACTION(
       "ScheduledActionAcquireLayerTexturesForMainThread", client, 1, 3);
-  EXPECT_ACTION("SetNeedsBeginImplFrame", client, 2, 3);
+  EXPECT_ACTION("SetNeedsBeginFrame", client, 2, 3);
   EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
   EXPECT_TRUE(client.needs_begin_impl_frame());
 
   // The compositor should not draw because textures are locked by main
   // thread.
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
   EXPECT_FALSE(client.needs_begin_impl_frame());
   EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
 
@@ -542,12 +550,13 @@ TEST(SchedulerTest, TextureAcquisitionCollision) {
   // the textures.
   client.Reset();
   scheduler->SetNeedsCommit();
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
   EXPECT_TRUE(client.needs_begin_impl_frame());
 
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_SINGLE_ACTION("ScheduledActionSendBeginMainFrame", client);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_ACTION("WillBeginImplFrame", client, 0, 2);
+  EXPECT_ACTION("ScheduledActionSendBeginMainFrame", client, 1, 2);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   client.Reset();
 
@@ -560,9 +569,9 @@ TEST(SchedulerTest, TextureAcquisitionCollision) {
   client.Reset();
 
   // Verify we draw on the next BeginImplFrame deadline
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_ACTION("ScheduledActionDrawAndSwapIfPossible", client, 0, 2);
-  EXPECT_ACTION("SetNeedsBeginImplFrame", client, 1, 2);
+  EXPECT_ACTION("SetNeedsBeginFrame", client, 1, 2);
   EXPECT_TRUE(client.needs_begin_impl_frame());
   EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
   client.Reset();
@@ -581,8 +590,8 @@ TEST(SchedulerTest, VisibilitySwitchWithTextureAcquisition) {
   scheduler->DidCreateAndInitializeOutputSurface();
 
   scheduler->SetNeedsCommit();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   scheduler->NotifyBeginMainFrameStarted();
   scheduler->NotifyReadyToCommit();
   scheduler->SetMainThreadNeedsLayerTextures();
@@ -603,8 +612,9 @@ TEST(SchedulerTest, VisibilitySwitchWithTextureAcquisition) {
   // compositor is waiting for first draw should result in a request
   // for a new frame in order to escape a deadlock.
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_SINGLE_ACTION("ScheduledActionSendBeginMainFrame", client);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_ACTION("WillBeginImplFrame", client, 0, 2);
+  EXPECT_ACTION("ScheduledActionSendBeginMainFrame", client, 1, 2);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
 }
 
@@ -651,22 +661,22 @@ TEST(SchedulerTest, RequestRedrawInsideDraw) {
   EXPECT_TRUE(client.needs_begin_impl_frame());
   EXPECT_EQ(0, client.num_draws());
 
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(1, client.num_draws());
   EXPECT_TRUE(scheduler->RedrawPending());
   EXPECT_TRUE(client.needs_begin_impl_frame());
 
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(2, client.num_draws());
   EXPECT_FALSE(scheduler->RedrawPending());
   EXPECT_TRUE(client.needs_begin_impl_frame());
 
   // We stop requesting BeginImplFrames after a BeginImplFrame where we don't
   // swap.
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(2, client.num_draws());
   EXPECT_FALSE(scheduler->RedrawPending());
   EXPECT_FALSE(client.needs_begin_impl_frame());
@@ -691,8 +701,8 @@ TEST(SchedulerTest, RequestRedrawInsideFailedDraw) {
   EXPECT_EQ(0, client.num_draws());
 
   // Fail the draw.
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(1, client.num_draws());
 
   // We have a commit pending and the draw failed, and we didn't lose the redraw
@@ -702,8 +712,8 @@ TEST(SchedulerTest, RequestRedrawInsideFailedDraw) {
   EXPECT_TRUE(client.needs_begin_impl_frame());
 
   // Fail the draw again.
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(2, client.num_draws());
   EXPECT_TRUE(scheduler->CommitPending());
   EXPECT_TRUE(scheduler->RedrawPending());
@@ -711,8 +721,8 @@ TEST(SchedulerTest, RequestRedrawInsideFailedDraw) {
 
   // Draw successfully.
   client.SetDrawWillHappen(true);
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(3, client.num_draws());
   EXPECT_TRUE(scheduler->CommitPending());
   EXPECT_FALSE(scheduler->RedrawPending());
@@ -772,17 +782,17 @@ TEST(SchedulerTest, RequestCommitInsideDraw) {
   EXPECT_TRUE(client.needs_begin_impl_frame());
 
   client.SetNeedsCommitOnNextDraw();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
   client.SetNeedsCommitOnNextDraw();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(1, client.num_draws());
   EXPECT_TRUE(scheduler->CommitPending());
   EXPECT_TRUE(client.needs_begin_impl_frame());
   scheduler->NotifyBeginMainFrameStarted();
   scheduler->NotifyReadyToCommit();
 
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(2, client.num_draws());
 
   EXPECT_FALSE(scheduler->RedrawPending());
@@ -791,8 +801,8 @@ TEST(SchedulerTest, RequestCommitInsideDraw) {
 
   // We stop requesting BeginImplFrames after a BeginImplFrame where we don't
   // swap.
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(2, client.num_draws());
   EXPECT_FALSE(scheduler->RedrawPending());
   EXPECT_FALSE(scheduler->CommitPending());
@@ -818,8 +828,8 @@ TEST(SchedulerTest, RequestCommitInsideFailedDraw) {
   EXPECT_EQ(0, client.num_draws());
 
   // Fail the draw.
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(1, client.num_draws());
 
   // We have a commit pending and the draw failed, and we didn't lose the commit
@@ -829,8 +839,9 @@ TEST(SchedulerTest, RequestCommitInsideFailedDraw) {
   EXPECT_TRUE(client.needs_begin_impl_frame());
 
   // Fail the draw again.
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(2, client.num_draws());
   EXPECT_TRUE(scheduler->CommitPending());
   EXPECT_TRUE(scheduler->RedrawPending());
@@ -838,8 +849,8 @@ TEST(SchedulerTest, RequestCommitInsideFailedDraw) {
 
   // Draw successfully.
   client.SetDrawWillHappen(true);
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(3, client.num_draws());
   EXPECT_TRUE(scheduler->CommitPending());
   EXPECT_FALSE(scheduler->RedrawPending());
@@ -863,8 +874,8 @@ TEST(SchedulerTest, NoSwapWhenDrawFails) {
 
   // Draw successfully, this starts a new frame.
   client.SetNeedsCommitOnNextDraw();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(1, client.num_draws());
 
   scheduler->SetNeedsRedraw();
@@ -874,8 +885,8 @@ TEST(SchedulerTest, NoSwapWhenDrawFails) {
   // Fail to draw, this should not start a frame.
   client.SetDrawWillHappen(false);
   client.SetNeedsCommitOnNextDraw();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  scheduler->OnBeginImplFrameDeadline();
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(2, client.num_draws());
 }
 
@@ -960,13 +971,13 @@ TEST(SchedulerTest, ManageTiles) {
   // We have no immediate actions to perform, so the BeginImplFrame should post
   // the deadline task.
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
 
   // On the deadline, he actions should have occured in the right order.
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(1, client.num_draws());
   EXPECT_TRUE(client.HasAction("ScheduledActionDrawAndSwapIfPossible"));
   EXPECT_TRUE(client.HasAction("ScheduledActionManageTiles"));
@@ -987,15 +998,15 @@ TEST(SchedulerTest, ManageTiles) {
   // We have no immediate actions to perform, so the BeginImplFrame should post
   // the deadline task.
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
 
   // Draw. The draw will trigger SetNeedsManageTiles, and
   // then the ManageTiles action will be triggered after the Draw.
   // Afterwards, neither a draw nor ManageTiles are pending.
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(1, client.num_draws());
   EXPECT_TRUE(client.HasAction("ScheduledActionDrawAndSwapIfPossible"));
   EXPECT_TRUE(client.HasAction("ScheduledActionManageTiles"));
@@ -1007,12 +1018,12 @@ TEST(SchedulerTest, ManageTiles) {
 
   // We need a BeginImplFrame where we don't swap to go idle.
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
-  EXPECT_SINGLE_ACTION("SetNeedsBeginImplFrame", client);
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
   EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
   EXPECT_EQ(0, client.num_draws());
 
@@ -1027,11 +1038,11 @@ TEST(SchedulerTest, ManageTiles) {
 
   // BeginImplFrame. There will be no draw, only ManageTiles.
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(0, client.num_draws());
   EXPECT_FALSE(client.HasAction("ScheduledActionDrawAndSwapIfPossible"));
   EXPECT_TRUE(client.HasAction("ScheduledActionManageTiles"));
@@ -1053,8 +1064,8 @@ TEST(SchedulerTest, ManageTilesOncePerFrame) {
   scheduler->SetNeedsManageTiles();
   scheduler->SetNeedsRedraw();
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
 
   EXPECT_TRUE(scheduler->ManageTilesPending());
@@ -1062,7 +1073,7 @@ TEST(SchedulerTest, ManageTilesOncePerFrame) {
   EXPECT_FALSE(scheduler->ManageTilesPending());
 
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(1, client.num_draws());
   EXPECT_TRUE(client.HasAction("ScheduledActionDrawAndSwapIfPossible"));
   EXPECT_FALSE(client.HasAction("ScheduledActionManageTiles"));
@@ -1074,12 +1085,12 @@ TEST(SchedulerTest, ManageTilesOncePerFrame) {
   scheduler->SetNeedsManageTiles();
   scheduler->SetNeedsRedraw();
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
 
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(1, client.num_draws());
   EXPECT_TRUE(client.HasAction("ScheduledActionDrawAndSwapIfPossible"));
   EXPECT_TRUE(client.HasAction("ScheduledActionManageTiles"));
@@ -1096,14 +1107,14 @@ TEST(SchedulerTest, ManageTilesOncePerFrame) {
   scheduler->SetNeedsManageTiles();
   scheduler->SetNeedsRedraw();
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
 
   EXPECT_TRUE(scheduler->ManageTilesPending());
 
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(1, client.num_draws());
   EXPECT_TRUE(client.HasAction("ScheduledActionDrawAndSwapIfPossible"));
   EXPECT_FALSE(client.HasAction("ScheduledActionManageTiles"));
@@ -1118,14 +1129,14 @@ TEST(SchedulerTest, ManageTilesOncePerFrame) {
   scheduler->SetNeedsManageTiles();
   scheduler->SetNeedsRedraw();
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
 
   EXPECT_TRUE(scheduler->ManageTilesPending());
 
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(1, client.num_draws());
   EXPECT_TRUE(client.HasAction("ScheduledActionDrawAndSwapIfPossible"));
   EXPECT_FALSE(client.HasAction("ScheduledActionManageTiles"));
@@ -1136,12 +1147,12 @@ TEST(SchedulerTest, ManageTilesOncePerFrame) {
   scheduler->SetNeedsManageTiles();
   scheduler->SetNeedsRedraw();
   client.Reset();
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
-  EXPECT_EQ(client.num_actions_(), 0);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
 
   client.Reset();
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(1, client.num_draws());
   EXPECT_TRUE(client.HasAction("ScheduledActionDrawAndSwapIfPossible"));
   EXPECT_TRUE(client.HasAction("ScheduledActionManageTiles"));
@@ -1163,9 +1174,8 @@ TEST(SchedulerTest, TriggerBeginFrameDeadlineEarly) {
   InitializeOutputSurfaceAndFirstCommit(scheduler, &client);
 
   client.Reset();
-  BeginFrameArgs impl_frame_args = BeginFrameArgs::CreateForTesting();
   scheduler->SetNeedsRedraw();
-  scheduler->BeginImplFrame(impl_frame_args);
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
 
   // The deadline should be zero since there is no work other than drawing
   // pending.
@@ -1221,9 +1231,9 @@ void MainFrameInHighLatencyMode(int64 begin_main_frame_to_commit_estimate_in_ms,
   client.Reset();
   scheduler->SetNeedsCommit();
   EXPECT_FALSE(scheduler->MainThreadIsInHighLatencyMode());
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
   EXPECT_FALSE(scheduler->MainThreadIsInHighLatencyMode());
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_TRUE(scheduler->MainThreadIsInHighLatencyMode());
   scheduler->NotifyBeginMainFrameStarted();
   scheduler->NotifyReadyToCommit();
@@ -1233,9 +1243,9 @@ void MainFrameInHighLatencyMode(int64 begin_main_frame_to_commit_estimate_in_ms,
   client.Reset();
   scheduler->SetNeedsCommit();
   EXPECT_TRUE(scheduler->MainThreadIsInHighLatencyMode());
-  scheduler->BeginImplFrame(BeginFrameArgs::CreateForTesting());
+  scheduler->BeginFrame(BeginFrameArgs::CreateForTesting());
   EXPECT_TRUE(scheduler->MainThreadIsInHighLatencyMode());
-  scheduler->OnBeginImplFrameDeadline();
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
   EXPECT_EQ(scheduler->MainThreadIsInHighLatencyMode(),
             should_send_begin_main_frame);
   EXPECT_EQ(client.HasAction("ScheduledActionSendBeginMainFrame"),
@@ -1290,9 +1300,9 @@ TEST(SchedulerTest, PollForCommitCompletion) {
   scheduler->NotifyReadyToCommit();
   scheduler->SetNeedsRedraw();
 
-  BeginFrameArgs impl_frame_args = BeginFrameArgs::CreateForTesting();
-  impl_frame_args.interval = base::TimeDelta::FromMilliseconds(1000);
-  scheduler->BeginImplFrame(impl_frame_args);
+  BeginFrameArgs frame_args = BeginFrameArgs::CreateForTesting();
+  frame_args.interval = base::TimeDelta::FromMilliseconds(1000);
+  scheduler->BeginFrame(frame_args);
 
   EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
   client.task_runner().RunPendingTasks();  // Run posted deadline.
@@ -1302,7 +1312,7 @@ TEST(SchedulerTest, PollForCommitCompletion) {
   // the NotifyReadyToCommit for now.
   EXPECT_FALSE(scheduler->CommitPending());
   scheduler->SetNeedsCommit();
-  scheduler->BeginImplFrame(impl_frame_args);
+  scheduler->BeginFrame(frame_args);
   EXPECT_TRUE(scheduler->CommitPending());
 
   // Spin the event loop a few times and make sure we get more
@@ -1311,7 +1321,7 @@ TEST(SchedulerTest, PollForCommitCompletion) {
 
   // Does three iterations to make sure that the timer is properly repeating.
   for (int i = 0; i < 3; ++i) {
-    EXPECT_EQ((impl_frame_args.interval * 2).InMicroseconds(),
+    EXPECT_EQ((frame_args.interval * 2).InMicroseconds(),
               client.task_runner().NextPendingTaskDelay().InMicroseconds())
         << *scheduler->StateAsValue();
     client.task_runner().RunPendingTasks();
@@ -1324,7 +1334,7 @@ TEST(SchedulerTest, PollForCommitCompletion) {
   // Do the same thing after BeginMainFrame starts but still before activation.
   scheduler->NotifyBeginMainFrameStarted();
   for (int i = 0; i < 3; ++i) {
-    EXPECT_EQ((impl_frame_args.interval * 2).InMicroseconds(),
+    EXPECT_EQ((frame_args.interval * 2).InMicroseconds(),
               client.task_runner().NextPendingTaskDelay().InMicroseconds())
         << *scheduler->StateAsValue();
     client.task_runner().RunPendingTasks();
@@ -1335,5 +1345,82 @@ TEST(SchedulerTest, PollForCommitCompletion) {
   }
 }
 
+TEST(SchedulerTest, BeginRetroFrame) {
+  FakeSchedulerClient client;
+  SchedulerSettings scheduler_settings;
+  Scheduler* scheduler = client.CreateScheduler(scheduler_settings);
+  scheduler->SetCanStart();
+  scheduler->SetVisible(true);
+  scheduler->SetCanDraw(true);
+  InitializeOutputSurfaceAndFirstCommit(scheduler, &client);
+
+  // SetNeedsCommit should begin the frame on the next BeginImplFrame.
+  client.Reset();
+  scheduler->SetNeedsCommit();
+  EXPECT_TRUE(client.needs_begin_impl_frame());
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
+  client.Reset();
+
+  // Create a BeginFrame with a long deadline to avoid race conditions.
+  // This is the first BeginFrame, which will be handled immediately.
+  BeginFrameArgs args = BeginFrameArgs::CreateForTesting();
+  args.deadline += base::TimeDelta::FromHours(1);

[Sami, 2014/04/08 11:25:25]

I wish all our deadlines were this long :)

+  scheduler->BeginFrame(args);
+
+  EXPECT_ACTION("WillBeginImplFrame", client, 0, 2);
+  EXPECT_ACTION("ScheduledActionSendBeginMainFrame", client, 1, 2);
+  EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
+  EXPECT_TRUE(client.needs_begin_impl_frame());
+  client.Reset();
+
+  // Queue BeginFrames while we are still handling the previous BeginFrame.
+  args.frame_time += base::TimeDelta::FromSeconds(1);
+  scheduler->BeginFrame(args);
+  args.frame_time += base::TimeDelta::FromSeconds(1);
+  scheduler->BeginFrame(args);
+
+  // If we don't swap on the deadline, we need to request another
+  // BeginImplFrame.
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
+  EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
+  EXPECT_TRUE(client.needs_begin_impl_frame());
+  client.Reset();
+
+  // NotifyReadyToCommit should trigger the commit.
+  scheduler->NotifyBeginMainFrameStarted();
+  scheduler->NotifyReadyToCommit();
+  EXPECT_SINGLE_ACTION("ScheduledActionCommit", client);
+  EXPECT_TRUE(client.needs_begin_impl_frame());
+  client.Reset();
+
+  // BeginImplFrame should prepare the draw.
+  client.task_runner().RunPendingTasks();  // Run posted BeginRetroFrame.
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
+  EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
+  EXPECT_TRUE(client.needs_begin_impl_frame());
+  client.Reset();
+
+  // BeginImplFrame deadline should draw.
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
+  EXPECT_ACTION("ScheduledActionDrawAndSwapIfPossible", client, 0, 2);
+  EXPECT_ACTION("SetNeedsBeginFrame", client, 1, 2);
+  EXPECT_FALSE(scheduler->BeginImplFrameDeadlinePending());
+  EXPECT_TRUE(client.needs_begin_impl_frame());
+  client.Reset();
+
+  // The following BeginImplFrame deadline should SetNeedsBeginFrame(false)
+  // to avoid excessive toggles.
+  client.task_runner().RunPendingTasks();  // Run posted BeginRetroFrame.
+  EXPECT_SINGLE_ACTION("WillBeginImplFrame", client);
+  EXPECT_TRUE(scheduler->BeginImplFrameDeadlinePending());
+  client.Reset();
+
+  client.task_runner().RunPendingTasks();  // Run posted deadline.
+  EXPECT_SINGLE_ACTION("SetNeedsBeginFrame", client);
+  EXPECT_FALSE(client.needs_begin_impl_frame());
+  client.Reset();
+}
+
 }  // namespace
 }  // namespace cc