cc: Adding testing for commits triggering NeedsBeginFrame when unable to draw.

cc/scheduler/scheduler_state_machine_unittest.cc

Index: cc/scheduler/scheduler_state_machine_unittest.cc
diff --git a/cc/scheduler/scheduler_state_machine_unittest.cc b/cc/scheduler/scheduler_state_machine_unittest.cc
index 40689811278d88fff5fb29b7d73968bf3d27a6ce..d7fde5317184fac4784d759af19b1058b91af98b 100644
--- a/cc/scheduler/scheduler_state_machine_unittest.cc
+++ b/cc/scheduler/scheduler_state_machine_unittest.cc
@@ -248,6 +248,35 @@ TEST(SchedulerStateMachineTest, TestNextActionBeginsMainFrameIfNeeded) {
 
     EXPECT_TRUE(state.BeginFrameNeeded());
 
+    // Expect nothing to happen until after OnBeginImplFrame.
+    EXPECT_COMMIT_STATE(SchedulerStateMachine::COMMIT_STATE_IDLE);
+    EXPECT_IMPL_FRAME_STATE(SchedulerStateMachine::BEGIN_IMPL_FRAME_STATE_IDLE);
+    EXPECT_ACTION(SchedulerStateMachine::ACTION_NONE);
+
+    state.OnBeginImplFrame();
+    EXPECT_ACTION_UPDATE_STATE(
+        SchedulerStateMachine::ACTION_SEND_BEGIN_MAIN_FRAME);
+  }
+
+  // If commit requested and can't draw, still begin a main frame.
+  {
+    StateMachine state(default_scheduler_settings);
+    state.SetCommitState(SchedulerStateMachine::COMMIT_STATE_IDLE);
+    state.SetCanStart();
+    state.UpdateState(state.NextAction());
+    state.CreateAndInitializeOutputSurfaceWithActivatedCommit();
+    state.SetNeedsRedraw(false);
+    state.SetVisible(true);
+    state.SetNeedsCommit();
+    state.SetCanDraw(false);
+
+    EXPECT_TRUE(state.BeginFrameNeeded());
+
+    // Expect nothing to happen until after OnBeginImplFrame.
+    EXPECT_COMMIT_STATE(SchedulerStateMachine::COMMIT_STATE_IDLE);
+    EXPECT_IMPL_FRAME_STATE(SchedulerStateMachine::BEGIN_IMPL_FRAME_STATE_IDLE);
+    EXPECT_ACTION(SchedulerStateMachine::ACTION_NONE);
+
     state.OnBeginImplFrame();
     EXPECT_ACTION_UPDATE_STATE(
         SchedulerStateMachine::ACTION_SEND_BEGIN_MAIN_FRAME);