cc: Unify use of DidSwapBuffers() and did_request_swap

Use OutputSurface::DidSwapBuffers() as the source of whether
we swapped or not.

R=brianderson@chromium.org
BUG=363414
TEST=cc_unittests

Review URL: https://codereview.chromium.org/246753008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@269738 0039d316-1c4b-4281-b951-d872f2087c98

8 files changed, 146 insertions, 145 deletions

diff --git a/cc/scheduler/draw_result.h b/cc/scheduler/draw_result.h
new file mode 100644
index 0000000..e63303c
--- /dev/null
+++ b/cc/scheduler/draw_result.h
@@ -0,0 +1,22 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CC_SCHEDULER_DRAW_RESULT_H_
+#define CC_SCHEDULER_DRAW_RESULT_H_
+
+namespace cc {
+
+enum DrawResult {
+    INVALID_RESULT,
+    DRAW_SUCCESS,
+    DRAW_ABORTED_CHECKERBOARD_ANIMATIONS,
+    DRAW_ABORTED_MISSING_HIGH_RES_CONTENT,
+    DRAW_ABORTED_CANT_READBACK,
+    DRAW_ABORTED_CONTEXT_LOST,
+    DRAW_ABORTED_CANT_DRAW,
+};
+
+}  // namespace cc
+
+#endif  // CC_SCHEDULER_DRAW_RESULT_H_
diff --git a/cc/scheduler/draw_swap_readback_result.h b/cc/scheduler/draw_swap_readback_result.h
deleted file mode 100644
index 852b897..0000000
--- a/cc/scheduler/draw_swap_readback_result.h
+++ /dev/null
@@ -1,38 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef CC_SCHEDULER_DRAW_SWAP_READBACK_RESULT_H_
-#define CC_SCHEDULER_DRAW_SWAP_READBACK_RESULT_H_
-
-namespace cc {
-
-struct DrawSwapReadbackResult {
-  enum DrawResult {
-    INVALID_RESULT,
-    DRAW_SUCCESS,
-    DRAW_ABORTED_CHECKERBOARD_ANIMATIONS,
-    DRAW_ABORTED_MISSING_HIGH_RES_CONTENT,
-    DRAW_ABORTED_CANT_READBACK,
-    DRAW_ABORTED_CONTEXT_LOST,
-    DRAW_ABORTED_CANT_DRAW,
-  };
-
-  DrawSwapReadbackResult()
-      : draw_result(INVALID_RESULT),
-        did_request_swap(false),
-        did_readback(false) {}
-  DrawSwapReadbackResult(DrawResult draw_result,
-                         bool did_request_swap,
-                         bool did_readback)
-      : draw_result(draw_result),
-        did_request_swap(did_request_swap),
-        did_readback(did_readback) {}
-  DrawResult draw_result;
-  bool did_request_swap;
-  bool did_readback;
-};
-
-}  // namespace cc
-
-#endif  // CC_SCHEDULER_DRAW_SWAP_READBACK_RESULT_H_
diff --git a/cc/scheduler/scheduler.cc b/cc/scheduler/scheduler.cc
index 9345561..7dea302 100644
--- a/cc/scheduler/scheduler.cc
+++ b/cc/scheduler/scheduler.cc
@@ -195,6 +195,10 @@ void Scheduler::SetMaxSwapsPending(int max) {
 
 void Scheduler::DidSwapBuffers() {
   state_machine_.DidSwapBuffers();
+
+  // Swap should not occur inside readback operation.
+  DCHECK(!IsInsideAction(SchedulerStateMachine::ACTION_DRAW_AND_READBACK));
+
   // There is no need to call ProcessScheduledActions here because
   // swapping should not trigger any new actions.
   if (!inside_process_scheduled_actions_) {
@@ -604,18 +608,8 @@ bool Scheduler::IsBeginMainFrameSent() const {
 }
 
 void Scheduler::DrawAndSwapIfPossible() {
-  DrawSwapReadbackResult result =
-      client_->ScheduledActionDrawAndSwapIfPossible();
-  state_machine_.DidDrawIfPossibleCompleted(result.draw_result);
-}
-
-void Scheduler::DrawAndSwapForced() {
-  client_->ScheduledActionDrawAndSwapForced();
-}
-
-void Scheduler::DrawAndReadback() {
-  DrawSwapReadbackResult result = client_->ScheduledActionDrawAndReadback();
-  DCHECK(!result.did_request_swap);
+  DrawResult result = client_->ScheduledActionDrawAndSwapIfPossible();
+  state_machine_.DidDrawIfPossibleCompleted(result);
 }
 
 void Scheduler::ProcessScheduledActions() {
@@ -659,14 +653,14 @@ void Scheduler::ProcessScheduledActions() {
         DrawAndSwapIfPossible();
         break;
       case SchedulerStateMachine::ACTION_DRAW_AND_SWAP_FORCED:
-        DrawAndSwapForced();
+        client_->ScheduledActionDrawAndSwapForced();
         break;
       case SchedulerStateMachine::ACTION_DRAW_AND_SWAP_ABORT:
         // No action is actually performed, but this allows the state machine to
         // advance out of its waiting to draw state without actually drawing.
         break;
       case SchedulerStateMachine::ACTION_DRAW_AND_READBACK:
-        DrawAndReadback();
+        client_->ScheduledActionDrawAndReadback();
         break;
       case SchedulerStateMachine::ACTION_BEGIN_OUTPUT_SURFACE_CREATION:
         client_->ScheduledActionBeginOutputSurfaceCreation();
diff --git a/cc/scheduler/scheduler.h b/cc/scheduler/scheduler.h
index b30f06e..5bf83fc 100644
--- a/cc/scheduler/scheduler.h
+++ b/cc/scheduler/scheduler.h
@@ -14,7 +14,7 @@
 #include "base/time/time.h"
 #include "cc/base/cc_export.h"
 #include "cc/output/begin_frame_args.h"
-#include "cc/scheduler/draw_swap_readback_result.h"
+#include "cc/scheduler/draw_result.h"
 #include "cc/scheduler/scheduler_settings.h"
 #include "cc/scheduler/scheduler_state_machine.h"
 #include "cc/scheduler/time_source.h"
@@ -30,9 +30,9 @@ class SchedulerClient {
   virtual void SetNeedsBeginFrame(bool enable) = 0;
   virtual void WillBeginImplFrame(const BeginFrameArgs& args) = 0;
   virtual void ScheduledActionSendBeginMainFrame() = 0;
-  virtual DrawSwapReadbackResult ScheduledActionDrawAndSwapIfPossible() = 0;
-  virtual DrawSwapReadbackResult ScheduledActionDrawAndSwapForced() = 0;
-  virtual DrawSwapReadbackResult ScheduledActionDrawAndReadback() = 0;
+  virtual DrawResult ScheduledActionDrawAndSwapIfPossible() = 0;
+  virtual DrawResult ScheduledActionDrawAndSwapForced() = 0;
+  virtual DrawResult ScheduledActionDrawAndReadback() = 0;
   virtual void ScheduledActionAnimate() = 0;
   virtual void ScheduledActionCommit() = 0;
   virtual void ScheduledActionUpdateVisibleTiles() = 0;
@@ -166,8 +166,6 @@ class CC_EXPORT Scheduler {
   void SetupPollingMechanisms(bool needs_begin_frame);
   void ActivatePendingTree();
   void DrawAndSwapIfPossible();
-  void DrawAndSwapForced();
-  void DrawAndReadback();
   void ProcessScheduledActions();
 
   bool CanCommitAndActivateBeforeDeadline() const;
diff --git a/cc/scheduler/scheduler_state_machine.cc b/cc/scheduler/scheduler_state_machine.cc
index 3ed18f6..84a6185 100644
--- a/cc/scheduler/scheduler_state_machine.cc
+++ b/cc/scheduler/scheduler_state_machine.cc
@@ -24,6 +24,7 @@ SchedulerStateMachine::SchedulerStateMachine(const SchedulerSettings& settings)
       current_frame_number_(0),
       last_frame_number_animate_performed_(-1),
       last_frame_number_swap_performed_(-1),
+      last_frame_number_swap_requested_(-1),
       last_frame_number_begin_main_frame_sent_(-1),
       last_frame_number_update_visible_tiles_was_called_(-1),
       manage_tiles_funnel_(0),
@@ -224,6 +225,8 @@ scoped_ptr<base::Value> SchedulerStateMachine::AsValue() const  {
                           last_frame_number_animate_performed_);
   minor_state->SetInteger("last_frame_number_swap_performed",
                           last_frame_number_swap_performed_);
+  minor_state->SetInteger("last_frame_number_swap_requested",
+                          last_frame_number_swap_requested_);
   minor_state->SetInteger(
       "last_frame_number_begin_main_frame_sent",
       last_frame_number_begin_main_frame_sent_);
@@ -292,6 +295,10 @@ bool SchedulerStateMachine::HasSwappedThisFrame() const {
   return current_frame_number_ == last_frame_number_swap_performed_;
 }
 
+bool SchedulerStateMachine::HasRequestedSwapThisFrame() const {
+  return current_frame_number_ == last_frame_number_swap_requested_;
+}
+
 bool SchedulerStateMachine::PendingDrawsShouldBeAborted() const {
   // These are all the cases where we normally cannot or do not want to draw
   // but, if needs_redraw_ is true and we do not draw to make forward progress,
@@ -370,8 +377,8 @@ bool SchedulerStateMachine::ShouldDraw() const {
   if (PendingDrawsShouldBeAborted())
     return active_tree_needs_first_draw_;
 
-  // After this line, we only want to swap once per frame.
-  if (HasSwappedThisFrame())
+  // After this line, we only want to send a swap request once per frame.
+  if (HasRequestedSwapThisFrame())
     return false;
 
   // Do not queue too many swaps.
@@ -793,7 +800,7 @@ void SchedulerStateMachine::UpdateStateOnDraw(bool did_request_swap) {
   active_tree_needs_first_draw_ = false;
 
   if (did_request_swap)
-    last_frame_number_swap_performed_ = current_frame_number_;
+    last_frame_number_swap_requested_ = current_frame_number_;
 }
 
 void SchedulerStateMachine::UpdateStateOnManageTiles() {
@@ -901,12 +908,12 @@ bool SchedulerStateMachine::ProactiveBeginFrameWanted() const {
   if (needs_manage_tiles_)
     return true;
 
-  // If we just swapped, it's likely that we are going to produce another
-  // frame soon. This helps avoid negative glitches in our
+  // If we just sent a swap request, it's likely that we are going to produce
+  // another frame soon. This helps avoid negative glitches in our
   // SetNeedsBeginFrame requests, which may propagate to the BeginImplFrame
   // provider and get sampled at an inopportune time, delaying the next
   // BeginImplFrame.
-  if (last_frame_number_swap_performed_ == current_frame_number_)
+  if (HasRequestedSwapThisFrame())
     return true;
 
   return false;
@@ -987,7 +994,7 @@ bool SchedulerStateMachine::MainThreadIsInHighLatencyMode() const {
 
   // If we just sent a BeginMainFrame and haven't hit the deadline yet, the main
   // thread is in a low latency mode.
-  if (last_frame_number_begin_main_frame_sent_ == current_frame_number_ &&
+  if (HasSentBeginMainFrameThisFrame() &&
       (begin_impl_frame_state_ == BEGIN_IMPL_FRAME_STATE_BEGIN_FRAME_STARTING ||
        begin_impl_frame_state_ == BEGIN_IMPL_FRAME_STATE_INSIDE_BEGIN_FRAME))
     return false;
@@ -995,9 +1002,7 @@ bool SchedulerStateMachine::MainThreadIsInHighLatencyMode() const {
   // If there's a commit in progress it must either be from the previous frame
   // or it started after the impl thread's deadline. In either case the main
   // thread is in high latency mode.
-  if (commit_state_ == COMMIT_STATE_BEGIN_MAIN_FRAME_SENT ||
-      commit_state_ == COMMIT_STATE_BEGIN_MAIN_FRAME_STARTED ||
-      commit_state_ == COMMIT_STATE_READY_TO_COMMIT)
+  if (CommitPending())
     return true;
 
   // Similarly, if there's a pending tree the main thread is in high latency
@@ -1011,11 +1016,10 @@ bool SchedulerStateMachine::MainThreadIsInHighLatencyMode() const {
 
   if (begin_impl_frame_state_ == BEGIN_IMPL_FRAME_STATE_INSIDE_DEADLINE) {
     // Even if there's a new active tree to draw at the deadline or we've just
-    // drawn it, it may have been triggered by a previous BeginImplFrame, in
+    // swapped it, it may have been triggered by a previous BeginImplFrame, in
     // which case the main thread is in a high latency mode.
-    return (active_tree_needs_first_draw_ ||
-            last_frame_number_swap_performed_ == current_frame_number_) &&
-           last_frame_number_begin_main_frame_sent_ != current_frame_number_;
+    return (active_tree_needs_first_draw_ || HasSwappedThisFrame()) &&
+           !HasSentBeginMainFrameThisFrame();
   }
 
   // If the active tree needs its first draw in any other state, we know the
@@ -1057,6 +1061,8 @@ void SchedulerStateMachine::SetMaxSwapsPending(int max) {
 void SchedulerStateMachine::DidSwapBuffers() {
   pending_swaps_++;
   DCHECK_LE(pending_swaps_, max_pending_swaps_);
+
+  last_frame_number_swap_performed_ = current_frame_number_;
 }
 
 void SchedulerStateMachine::SetSwapUsedIncompleteTile(
@@ -1074,23 +1080,22 @@ void SchedulerStateMachine::SetSmoothnessTakesPriority(
   smoothness_takes_priority_ = smoothness_takes_priority;
 }
 
-void SchedulerStateMachine::DidDrawIfPossibleCompleted(
-    DrawSwapReadbackResult::DrawResult result) {
+void SchedulerStateMachine::DidDrawIfPossibleCompleted(DrawResult result) {
   switch (result) {
-    case DrawSwapReadbackResult::INVALID_RESULT:
-      NOTREACHED() << "Uninitialized DrawSwapReadbackResult.";
+    case INVALID_RESULT:
+      NOTREACHED() << "Uninitialized DrawResult.";
       break;
-    case DrawSwapReadbackResult::DRAW_ABORTED_CANT_DRAW:
-    case DrawSwapReadbackResult::DRAW_ABORTED_CANT_READBACK:
-    case DrawSwapReadbackResult::DRAW_ABORTED_CONTEXT_LOST:
+    case DRAW_ABORTED_CANT_DRAW:
+    case DRAW_ABORTED_CANT_READBACK:
+    case DRAW_ABORTED_CONTEXT_LOST:
       NOTREACHED() << "Invalid return value from DrawAndSwapIfPossible:"
                    << result;
       break;
-    case DrawSwapReadbackResult::DRAW_SUCCESS:
+    case DRAW_SUCCESS:
       consecutive_checkerboard_animations_ = 0;
       forced_redraw_state_ = FORCED_REDRAW_STATE_IDLE;
       break;
-    case DrawSwapReadbackResult::DRAW_ABORTED_CHECKERBOARD_ANIMATIONS:
+    case DRAW_ABORTED_CHECKERBOARD_ANIMATIONS:
       needs_redraw_ = true;
 
       // If we're already in the middle of a redraw, we don't need to
@@ -1109,7 +1114,7 @@ void SchedulerStateMachine::DidDrawIfPossibleCompleted(
         forced_redraw_state_ = FORCED_REDRAW_STATE_WAITING_FOR_COMMIT;
       }
       break;
-    case DrawSwapReadbackResult::DRAW_ABORTED_MISSING_HIGH_RES_CONTENT:
+    case DRAW_ABORTED_MISSING_HIGH_RES_CONTENT:
       // It's not clear whether this missing content is because of missing
       // pictures (which requires a commit) or because of memory pressure
       // removing textures (which might not).  To be safe, request a commit
diff --git a/cc/scheduler/scheduler_state_machine.h b/cc/scheduler/scheduler_state_machine.h
index ff032b6..9df9c08 100644
--- a/cc/scheduler/scheduler_state_machine.h
+++ b/cc/scheduler/scheduler_state_machine.h
@@ -12,7 +12,7 @@
 #include "base/time/time.h"
 #include "cc/base/cc_export.h"
 #include "cc/output/begin_frame_args.h"
-#include "cc/scheduler/draw_swap_readback_result.h"
+#include "cc/scheduler/draw_result.h"
 #include "cc/scheduler/scheduler_settings.h"
 
 namespace base {
@@ -193,7 +193,7 @@ class CC_EXPORT SchedulerStateMachine {
   bool smoothness_takes_priority() const { return smoothness_takes_priority_; }
 
   // Indicates whether ACTION_DRAW_AND_SWAP_IF_POSSIBLE drew to the screen.
-  void DidDrawIfPossibleCompleted(DrawSwapReadbackResult::DrawResult result);
+  void DidDrawIfPossibleCompleted(DrawResult result);
 
   // Indicates that a new commit flow needs to be performed, either to pull
   // updates from the main thread to the impl, or to push deltas from the impl
@@ -271,6 +271,7 @@ class CC_EXPORT SchedulerStateMachine {
   void AdvanceCurrentFrameNumber();
   bool HasSentBeginMainFrameThisFrame() const;
   bool HasUpdatedVisibleTilesThisFrame() const;
+  bool HasRequestedSwapThisFrame() const;
   bool HasSwappedThisFrame() const;
 
   void UpdateStateOnCommit(bool commit_was_aborted);
@@ -292,6 +293,7 @@ class CC_EXPORT SchedulerStateMachine {
   int current_frame_number_;
   int last_frame_number_animate_performed_;
   int last_frame_number_swap_performed_;
+  int last_frame_number_swap_requested_;
   int last_frame_number_begin_main_frame_sent_;
   int last_frame_number_update_visible_tiles_was_called_;
 
diff --git a/cc/scheduler/scheduler_state_machine_unittest.cc b/cc/scheduler/scheduler_state_machine_unittest.cc
index 64d1c25..b39d50d 100644
--- a/cc/scheduler/scheduler_state_machine_unittest.cc
+++ b/cc/scheduler/scheduler_state_machine_unittest.cc
@@ -255,6 +255,8 @@ TEST(SchedulerStateMachineTest, MainFrameBeforeDrawDisabled) {
   state.OnBeginImplFrameDeadline();
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
   EXPECT_EQ(state.CommitState(), SchedulerStateMachine::COMMIT_STATE_IDLE);
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_SEND_BEGIN_MAIN_FRAME);
@@ -327,6 +329,8 @@ TEST(SchedulerStateMachineTest, MainFrameBeforeActivationEnabled) {
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_ANIMATE);
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_COMMIT);
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
   EXPECT_EQ(state.CommitState(), SchedulerStateMachine::COMMIT_STATE_IDLE);
@@ -352,14 +356,15 @@ TEST(SchedulerStateMachineTest,
   // We're drawing now.
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
 
   EXPECT_FALSE(state.RedrawPending());
   EXPECT_FALSE(state.CommitPending());
 
   // Failing the draw makes us require a commit.
-  state.DidDrawIfPossibleCompleted(
-      DrawSwapReadbackResult::DRAW_ABORTED_CHECKERBOARD_ANIMATIONS);
+  state.DidDrawIfPossibleCompleted(DRAW_ABORTED_CHECKERBOARD_ANIMATIONS);
   state.OnBeginImplFrame(CreateBeginFrameArgsForTesting());
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_ANIMATE);
   EXPECT_ACTION_UPDATE_STATE(
@@ -386,13 +391,14 @@ TEST(SchedulerStateMachineTest, TestFailedDrawForMissingHighResNeedsCommit) {
   state.OnBeginImplFrameDeadline();
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
   EXPECT_FALSE(state.RedrawPending());
   EXPECT_FALSE(state.CommitPending());
 
   // Missing high res content requires a commit (but not a redraw)
-  state.DidDrawIfPossibleCompleted(
-      DrawSwapReadbackResult::DRAW_ABORTED_MISSING_HIGH_RES_CONTENT);
+  state.DidDrawIfPossibleCompleted(DRAW_ABORTED_MISSING_HIGH_RES_CONTENT);
   state.OnBeginImplFrame(CreateBeginFrameArgsForTesting());
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_SEND_BEGIN_MAIN_FRAME);
@@ -421,6 +427,8 @@ TEST(SchedulerStateMachineTest,
   // We're drawing now.
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
   EXPECT_FALSE(state.RedrawPending());
   EXPECT_FALSE(state.CommitPending());
@@ -431,8 +439,7 @@ TEST(SchedulerStateMachineTest,
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
 
   // Failing the draw for animation checkerboards makes us require a commit.
-  state.DidDrawIfPossibleCompleted(
-      DrawSwapReadbackResult::DRAW_ABORTED_CHECKERBOARD_ANIMATIONS);
+  state.DidDrawIfPossibleCompleted(DRAW_ABORTED_CHECKERBOARD_ANIMATIONS);
   state.OnBeginImplFrame(CreateBeginFrameArgsForTesting());
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_ANIMATE);
   EXPECT_ACTION_UPDATE_STATE(
@@ -470,8 +477,7 @@ void TestFailedDrawsEventuallyForceDrawAfterNextCommit(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
 
   // Fail the draw.
-  state.DidDrawIfPossibleCompleted(
-      DrawSwapReadbackResult::DRAW_ABORTED_CHECKERBOARD_ANIMATIONS);
+  state.DidDrawIfPossibleCompleted(DRAW_ABORTED_CHECKERBOARD_ANIMATIONS);
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
   EXPECT_TRUE(state.BeginFrameNeeded());
   EXPECT_TRUE(state.RedrawPending());
@@ -497,6 +503,8 @@ void TestFailedDrawsEventuallyForceDrawAfterNextCommit(
   state.OnBeginImplFrameDeadline();
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_FORCED);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
 }
 
 TEST(SchedulerStateMachineTest,
@@ -544,10 +552,8 @@ TEST(SchedulerStateMachineTest, TestFailedDrawsDoNotRestartForcedDraw) {
 
   // Fail the draw enough times to force a redraw,
   // then once more for good measure.
-  for (int i = 0; i < draw_limit + 1; ++i) {
-    state.DidDrawIfPossibleCompleted(
-        DrawSwapReadbackResult::DRAW_ABORTED_CHECKERBOARD_ANIMATIONS);
-  }
+  for (int i = 0; i < draw_limit + 1; ++i)
+    state.DidDrawIfPossibleCompleted(DRAW_ABORTED_CHECKERBOARD_ANIMATIONS);
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
   EXPECT_TRUE(state.BeginFrameNeeded());
   EXPECT_TRUE(state.RedrawPending());
@@ -569,10 +575,8 @@ TEST(SchedulerStateMachineTest, TestFailedDrawsDoNotRestartForcedDraw) {
 
   // After failing additional draws, we should still be in a forced
   // redraw, but not back in WAITING_FOR_COMMIT.
-  for (int i = 0; i < draw_limit + 1; ++i) {
-    state.DidDrawIfPossibleCompleted(
-        DrawSwapReadbackResult::DRAW_ABORTED_CHECKERBOARD_ANIMATIONS);
-  }
+  for (int i = 0; i < draw_limit + 1; ++i)
+    state.DidDrawIfPossibleCompleted(DRAW_ABORTED_CHECKERBOARD_ANIMATIONS);
   EXPECT_TRUE(state.RedrawPending());
   EXPECT_TRUE(state.ForcedRedrawState() ==
     SchedulerStateMachine::FORCED_REDRAW_STATE_WAITING_FOR_ACTIVATION);
@@ -599,8 +603,7 @@ TEST(SchedulerStateMachineTest, TestFailedDrawIsRetriedInNextBeginImplFrame) {
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
 
   // Failing the draw for animation checkerboards makes us require a commit.
-  state.DidDrawIfPossibleCompleted(
-      DrawSwapReadbackResult::DRAW_ABORTED_CHECKERBOARD_ANIMATIONS);
+  state.DidDrawIfPossibleCompleted(DRAW_ABORTED_CHECKERBOARD_ANIMATIONS);
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_SEND_BEGIN_MAIN_FRAME);
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
@@ -617,6 +620,8 @@ TEST(SchedulerStateMachineTest, TestFailedDrawIsRetriedInNextBeginImplFrame) {
   state.OnBeginImplFrameDeadline();
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
 }
 
@@ -639,7 +644,9 @@ TEST(SchedulerStateMachineTest, TestDoestDrawTwiceInSameFrame) {
   state.OnBeginImplFrameDeadline();
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
-  state.DidDrawIfPossibleCompleted(DrawSwapReadbackResult::DRAW_SUCCESS);
+  state.DidSwapBuffers();
+  state.DidDrawIfPossibleCompleted(DRAW_SUCCESS);
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
 
   // Before the next BeginImplFrame, set needs redraw again.
@@ -657,7 +664,9 @@ TEST(SchedulerStateMachineTest, TestDoestDrawTwiceInSameFrame) {
   state.OnBeginImplFrameDeadline();
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
-  state.DidDrawIfPossibleCompleted(DrawSwapReadbackResult::DRAW_SUCCESS);
+  state.DidSwapBuffers();
+  state.DidDrawIfPossibleCompleted(DRAW_SUCCESS);
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
 
   // We just swapped, so we should proactively request another BeginImplFrame.
@@ -904,7 +913,9 @@ void TestSetNeedsCommitIsNotLost(bool main_frame_before_draw_enabled) {
   EXPECT_TRUE(state.active_tree_needs_first_draw());
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
-  state.DidDrawIfPossibleCompleted(DrawSwapReadbackResult::DRAW_SUCCESS);
+  state.DidSwapBuffers();
+  state.DidDrawIfPossibleCompleted(DRAW_SUCCESS);
+  state.DidSwapBuffersComplete();
   if (!main_frame_before_draw_enabled) {
     EXPECT_ACTION_UPDATE_STATE(
         SchedulerStateMachine::ACTION_SEND_BEGIN_MAIN_FRAME);
@@ -962,7 +973,9 @@ TEST(SchedulerStateMachineTest, TestFullCycle) {
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_ANIMATE);
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
-  state.DidDrawIfPossibleCompleted(DrawSwapReadbackResult::DRAW_SUCCESS);
+  state.DidSwapBuffers();
+  state.DidDrawIfPossibleCompleted(DRAW_SUCCESS);
+  state.DidSwapBuffersComplete();
 
   // Should be synchronized, no draw needed, no action needed.
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
@@ -1014,7 +1027,9 @@ TEST(SchedulerStateMachineTest, TestFullCycleWithCommitRequestInbetween) {
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_ANIMATE);
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
-  state.DidDrawIfPossibleCompleted(DrawSwapReadbackResult::DRAW_SUCCESS);
+  state.DidSwapBuffers();
+  state.DidDrawIfPossibleCompleted(DRAW_SUCCESS);
+  state.DidSwapBuffersComplete();
 
   // Should be synchronized, no draw needed, no action needed.
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
@@ -1125,6 +1140,8 @@ TEST(SchedulerStateMachineTest, AbortBeginMainFrameAndCancelCommit) {
   state.OnBeginImplFrameDeadline();
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
 
   // Verify another commit doesn't start on another frame either.
   EXPECT_EQ(SchedulerStateMachine::COMMIT_STATE_IDLE, state.CommitState());
@@ -1281,6 +1298,8 @@ TEST(SchedulerStateMachineTest, TestContextLostWhileCommitInProgress) {
   state.OnBeginImplFrameDeadline();
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
 
   // Cause a lost context while the BeginMainFrame is in flight.
@@ -1346,6 +1365,8 @@ TEST(SchedulerStateMachineTest,
   state.OnBeginImplFrameDeadline();
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
 
   // Cause a lost context while the BeginMainFrame is in flight.
@@ -1404,6 +1425,8 @@ TEST(SchedulerStateMachineTest,
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_ANIMATE);
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
 }
 
@@ -1676,6 +1699,8 @@ void TestForceCommitWhenReplacementActivationInProgress(
   state.OnBeginImplFrameDeadline();
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
   if (!settings.main_frame_before_draw_enabled) {
     // New replacement commit is scheduled.
     EXPECT_ACTION_UPDATE_STATE(
@@ -1715,6 +1740,8 @@ void TestForceCommitWhenReplacementActivationInProgress(
   state.OnBeginImplFrameDeadline();
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
   EXPECT_EQ(SchedulerStateMachine::READBACK_STATE_IDLE, state.readback_state());
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
 }
@@ -1787,6 +1814,8 @@ TEST(SchedulerStateMachineTest,
   state.OnBeginImplFrameDeadline();
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_DRAW_AND_SWAP_IF_POSSIBLE);
+  state.DidSwapBuffers();
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(
       SchedulerStateMachine::ACTION_NONE);
 
@@ -1856,7 +1885,9 @@ TEST(SchedulerStateMachineTest, TestImmediateFinishCommit) {
   EXPECT_TRUE(state.active_tree_needs_first_draw());
 
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_DRAW_AND_READBACK);
-  state.DidDrawIfPossibleCompleted(DrawSwapReadbackResult::DRAW_SUCCESS);
+  state.DidSwapBuffers();
+  state.DidDrawIfPossibleCompleted(DRAW_SUCCESS);
+  state.DidSwapBuffersComplete();
 
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
 
@@ -1892,7 +1923,9 @@ TEST(SchedulerStateMachineTest, TestImmediateFinishCommitDuringCommit) {
   EXPECT_TRUE(state.active_tree_needs_first_draw());
 
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_DRAW_AND_READBACK);
-  state.DidDrawIfPossibleCompleted(DrawSwapReadbackResult::DRAW_SUCCESS);
+  state.DidSwapBuffers();
+  state.DidDrawIfPossibleCompleted(DRAW_SUCCESS);
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
 
   // Should be waiting for the normal BeginMainFrame.
@@ -1926,7 +1959,9 @@ TEST(SchedulerStateMachineTest, ImmediateBeginMainFrameAbortedWhileInvisible) {
   EXPECT_TRUE(state.active_tree_needs_first_draw());
 
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_DRAW_AND_READBACK);
-  state.DidDrawIfPossibleCompleted(DrawSwapReadbackResult::DRAW_SUCCESS);
+  state.DidSwapBuffers();
+  state.DidDrawIfPossibleCompleted(DRAW_SUCCESS);
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
 
   // Should be waiting for BeginMainFrame.
@@ -1967,7 +2002,9 @@ TEST(SchedulerStateMachineTest, ImmediateFinishCommitWhileCantDraw) {
   EXPECT_TRUE(state.active_tree_needs_first_draw());
 
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_DRAW_AND_READBACK);
-  state.DidDrawIfPossibleCompleted(DrawSwapReadbackResult::DRAW_SUCCESS);
+  state.DidSwapBuffers();
+  state.DidDrawIfPossibleCompleted(DRAW_SUCCESS);
+  state.DidSwapBuffersComplete();
   EXPECT_ACTION_UPDATE_STATE(SchedulerStateMachine::ACTION_NONE);
 }
 
diff --git a/cc/scheduler/scheduler_unittest.cc b/cc/scheduler/scheduler_unittest.cc
index d307f96..c3d9f38 100644
--- a/cc/scheduler/scheduler_unittest.cc
+++ b/cc/scheduler/scheduler_unittest.cc
@@ -114,16 +114,12 @@ class FakeSchedulerClient : public SchedulerClient {
     actions_.push_back("ScheduledActionAnimate");
     states_.push_back(scheduler_->AsValue().release());
   }
-  virtual DrawSwapReadbackResult ScheduledActionDrawAndSwapIfPossible()
-      OVERRIDE {
+  virtual DrawResult ScheduledActionDrawAndSwapIfPossible() OVERRIDE {
     actions_.push_back("ScheduledActionDrawAndSwapIfPossible");
     states_.push_back(scheduler_->AsValue().release());
     num_draws_++;
-    bool did_readback = false;
-    DrawSwapReadbackResult::DrawResult result =
-        draw_will_happen_
-            ? DrawSwapReadbackResult::DRAW_SUCCESS
-            : DrawSwapReadbackResult::DRAW_ABORTED_CHECKERBOARD_ANIMATIONS;
+    DrawResult result =
+        draw_will_happen_ ? DRAW_SUCCESS : DRAW_ABORTED_CHECKERBOARD_ANIMATIONS;
     bool swap_will_happen =
         draw_will_happen_ && swap_will_happen_if_draw_happens_;
     if (swap_will_happen) {
@@ -131,26 +127,17 @@ class FakeSchedulerClient : public SchedulerClient {
       if (automatic_swap_ack_)
         scheduler_->DidSwapBuffersComplete();
     }
-    return DrawSwapReadbackResult(
-        result,
-        draw_will_happen_ && swap_will_happen_if_draw_happens_,
-        did_readback);
+    return result;
   }
-  virtual DrawSwapReadbackResult ScheduledActionDrawAndSwapForced() OVERRIDE {
+  virtual DrawResult ScheduledActionDrawAndSwapForced() OVERRIDE {
     actions_.push_back("ScheduledActionDrawAndSwapForced");
     states_.push_back(scheduler_->AsValue().release());
-    bool did_request_swap = swap_will_happen_if_draw_happens_;
-    bool did_readback = false;
-    return DrawSwapReadbackResult(
-        DrawSwapReadbackResult::DRAW_SUCCESS, did_request_swap, did_readback);
+    return DRAW_SUCCESS;
   }
-  virtual DrawSwapReadbackResult ScheduledActionDrawAndReadback() OVERRIDE {
+  virtual DrawResult ScheduledActionDrawAndReadback() OVERRIDE {
     actions_.push_back("ScheduledActionDrawAndReadback");
     states_.push_back(scheduler_->AsValue().release());
-    bool did_request_swap = false;
-    bool did_readback = true;
-    return DrawSwapReadbackResult(
-        DrawSwapReadbackResult::DRAW_SUCCESS, did_request_swap, did_readback);
+    return DRAW_SUCCESS;
   }
   virtual void ScheduledActionCommit() OVERRIDE {
     actions_.push_back("ScheduledActionCommit");
@@ -395,7 +382,7 @@ TEST(SchedulerTest, RequestCommitAfterBeginMainFrameSent) {
 class SchedulerClientThatsetNeedsDrawInsideDraw : public FakeSchedulerClient {
  public:
   virtual void ScheduledActionSendBeginMainFrame() OVERRIDE {}
-  virtual DrawSwapReadbackResult ScheduledActionDrawAndSwapIfPossible()
+  virtual DrawResult ScheduledActionDrawAndSwapIfPossible()
       OVERRIDE {
     // Only SetNeedsRedraw the first time this is called
     if (!num_draws_)
@@ -403,12 +390,9 @@ class SchedulerClientThatsetNeedsDrawInsideDraw : public FakeSchedulerClient {
     return FakeSchedulerClient::ScheduledActionDrawAndSwapIfPossible();
   }
 
-  virtual DrawSwapReadbackResult ScheduledActionDrawAndSwapForced() OVERRIDE {
+  virtual DrawResult ScheduledActionDrawAndSwapForced() OVERRIDE {
     NOTREACHED();
-    bool did_request_swap = true;
-    bool did_readback = false;
-    return DrawSwapReadbackResult(
-        DrawSwapReadbackResult::DRAW_SUCCESS, did_request_swap, did_readback);
+    return DRAW_SUCCESS;
   }
 
   virtual void ScheduledActionCommit() OVERRIDE {}
@@ -509,7 +493,7 @@ class SchedulerClientThatSetNeedsCommitInsideDraw : public FakeSchedulerClient {
       : set_needs_commit_on_next_draw_(false) {}
 
   virtual void ScheduledActionSendBeginMainFrame() OVERRIDE {}
-  virtual DrawSwapReadbackResult ScheduledActionDrawAndSwapIfPossible()
+  virtual DrawResult ScheduledActionDrawAndSwapIfPossible()
       OVERRIDE {
     // Only SetNeedsCommit the first time this is called
     if (set_needs_commit_on_next_draw_) {
@@ -519,12 +503,9 @@ class SchedulerClientThatSetNeedsCommitInsideDraw : public FakeSchedulerClient {
     return FakeSchedulerClient::ScheduledActionDrawAndSwapIfPossible();
   }
 
-  virtual DrawSwapReadbackResult ScheduledActionDrawAndSwapForced() OVERRIDE {
+  virtual DrawResult ScheduledActionDrawAndSwapForced() OVERRIDE {
     NOTREACHED();
-    bool did_request_swap = false;
-    bool did_readback = false;
-    return DrawSwapReadbackResult(
-        DrawSwapReadbackResult::DRAW_SUCCESS, did_request_swap, did_readback);
+    return DRAW_SUCCESS;
   }
 
   virtual void ScheduledActionCommit() OVERRIDE {}
@@ -713,7 +694,7 @@ TEST(SchedulerTest, BackToBackReadbackAllowed) {
 
 class SchedulerClientNeedsManageTilesInDraw : public FakeSchedulerClient {
  public:
-  virtual DrawSwapReadbackResult ScheduledActionDrawAndSwapIfPossible()
+  virtual DrawResult ScheduledActionDrawAndSwapIfPossible()
       OVERRIDE {
     scheduler_->SetNeedsManageTiles();
     return FakeSchedulerClient::ScheduledActionDrawAndSwapIfPossible();