cc: Add scheduler support for invalidating content on impl thread.

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 f3bf54b89eb0b412472126725fd315fe5ac97e16..e164c7334bbf0e3244f8ab9c1b2af49314550f33 100644
--- a/cc/scheduler/scheduler_unittest.cc
+++ b/cc/scheduler/scheduler_unittest.cc
@@ -171,6 +171,9 @@ class FakeSchedulerClient : public SchedulerClient,
     actions_.push_back("ScheduledActionInvalidateCompositorFrameSink");
     states_.push_back(scheduler_->AsValue());
   }
+  void ScheduledActionPerformImplSideInvalidation() override {
+    PushAction("ScheduledActionPerformImplSideInvalidation");
+  }
 
   void SendBeginMainFrameNotExpectedSoon() override {
     PushAction("SendBeginMainFrameNotExpectedSoon");
@@ -3183,6 +3186,47 @@ TEST_F(SchedulerTest, NoCompositorFrameSinkCreationWhileCommitPending) {
                        client_);
 }
 
+TEST_F(SchedulerTest, ImplSideInvalidationsMergedWithCommit) {

[sunnyps, 2017/02/20 23:19:22]

I don't understand what this is testing. If SetNeedsImplSideInvalidation was a
nop, this test would still pass.

[Khushal, 2017/02/21 09:43:45]

Its testing that if there is a main frame request, then an impl-side
invalidation request *should* be a no-op, since they should get merged with the
commit and we shouldn't see any other actions. The only action should be the
commit. Do you have a suggestion on re-structuring the test for this, or do you
think its unnecessary?

+  SetUpScheduler(EXTERNAL_BFS);
+
+  // Request a main frame and invalidation, the only action run should be
+  // sending the main frame.
+  scheduler_->SetNeedsBeginMainFrame();
+  scheduler_->SetNeedsImplSideInvalidation();
+  client_->Reset();
+  EXPECT_SCOPED(AdvanceFrame());
+  EXPECT_ACTION("WillBeginImplFrame", client_, 0, 2);
+  EXPECT_ACTION("ScheduledActionSendBeginMainFrame", client_, 1, 2);
+
+  // Respond with a commit. The scheduler should only perform the commit
+  // actions since the impl-side invalidation request will be merged with the
+  // commit.
+  client_->Reset();
+  scheduler_->NotifyBeginMainFrameStarted(base::TimeTicks::Now());
+  scheduler_->NotifyReadyToCommit();
+  EXPECT_SINGLE_ACTION("ScheduledActionCommit", client_);
+}
+
+TEST_F(SchedulerTest, AbortedCommitsTriggerImplSideInvalidations) {
+  SetUpScheduler(EXTERNAL_BFS);
+
+  // Request a main frame and invalidation.
+  scheduler_->SetNeedsBeginMainFrame();
+  scheduler_->SetNeedsImplSideInvalidation();
+  client_->Reset();
+  EXPECT_SCOPED(AdvanceFrame());
+  EXPECT_ACTION("WillBeginImplFrame", client_, 0, 2);
+  EXPECT_ACTION("ScheduledActionSendBeginMainFrame", client_, 1, 2);
+
+  // Abort the main frame and request another one, the impl-side invalidations
+  // should not be blocked on the main frame.
+  client_->Reset();
+  scheduler_->NotifyBeginMainFrameStarted(base::TimeTicks::Now());
+  scheduler_->BeginMainFrameAborted(CommitEarlyOutReason::FINISHED_NO_UPDATES);
+  scheduler_->SetNeedsBeginMainFrame();
+  EXPECT_SINGLE_ACTION("ScheduledActionPerformImplSideInvalidation", client_);
+}
+
 // The three letters appeneded to each version of this test mean the following:s
 // tree_priority: B = both trees same priority; A = active tree priority;
 // scroll_handler_state: H = affects scroll handler; N = does not affect scroll