cc: Redraw incomplete frames when new texture uploads finish

cc/scheduler_state_machine.cc

Index: cc/scheduler_state_machine.cc
diff --git a/cc/scheduler_state_machine.cc b/cc/scheduler_state_machine.cc
index 5d6229703f8fd5285d6c4bf5e0b9d09e884f6a59..01f2f0098baee6b40e627047db0f7f76965190ce 100644
--- a/cc/scheduler_state_machine.cc
+++ b/cc/scheduler_state_machine.cc
@@ -15,9 +15,11 @@ SchedulerStateMachine::SchedulerStateMachine(const SchedulerSettings& settings)
     , m_currentFrameNumber(0)
     , m_lastFrameNumberWhereDrawWasCalled(-1)
     , m_lastFrameNumberWhereTreeActivationAttempted(-1)
+    , m_lastFrameNumberWhereCheckForCompletedTexturesCalled(-1)
     , m_consecutiveFailedDraws(0)
     , m_maximumNumberOfFailedDrawsBeforeDrawIsForced(3)
     , m_needsRedraw(false)
+    , m_swapUsedIncompleteTexture(false)
     , m_needsForcedRedraw(false)
     , m_needsForcedRedrawAfterNextCommit(false)
     , m_needsCommit(false)
@@ -38,12 +40,16 @@ SchedulerStateMachine::SchedulerStateMachine(const SchedulerSettings& settings)
 std::string SchedulerStateMachine::toString()
 {
     std::string str;
+    base::StringAppendF(&str, "m_settings.implSidePainting = %d; ", m_settings.implSidePainting);
     base::StringAppendF(&str, "m_commitState = %d; ", m_commitState);
     base::StringAppendF(&str, "m_currentFrameNumber = %d; ", m_currentFrameNumber);
     base::StringAppendF(&str, "m_lastFrameNumberWhereDrawWasCalled = %d; ", m_lastFrameNumberWhereDrawWasCalled);
+    base::StringAppendF(&str, "m_lastFrameNumberWhereTreeActivationAttempted = %d; ", m_lastFrameNumberWhereTreeActivationAttempted);
+    base::StringAppendF(&str, "m_lastFrameNumberWhereCheckForCompletedTexturesCalled = %d; ", m_lastFrameNumberWhereCheckForCompletedTexturesCalled);
     base::StringAppendF(&str, "m_consecutiveFailedDraws = %d; ", m_consecutiveFailedDraws);
     base::StringAppendF(&str, "m_maximumNumberOfFailedDrawsBeforeDrawIsForced = %d; ", m_maximumNumberOfFailedDrawsBeforeDrawIsForced);
     base::StringAppendF(&str, "m_needsRedraw = %d; ", m_needsRedraw);
+    base::StringAppendF(&str, "m_swapUsedIncompleteTexture = %d; ", m_swapUsedIncompleteTexture);
     base::StringAppendF(&str, "m_needsForcedRedraw = %d; ", m_needsForcedRedraw);
     base::StringAppendF(&str, "m_needsForcedRedrawAfterNextCommit = %d; ", m_needsForcedRedrawAfterNextCommit);
     base::StringAppendF(&str, "m_needsCommit = %d; ", m_needsCommit);
@@ -71,6 +77,12 @@ bool SchedulerStateMachine::hasAttemptedTreeActivationThisFrame() const
     return m_currentFrameNumber == m_lastFrameNumberWhereTreeActivationAttempted;
 }
 
+bool SchedulerStateMachine::hasCheckedForCompletedTexturesThisFrame() const
+{
+    return m_currentFrameNumber ==
+           m_lastFrameNumberWhereCheckForCompletedTexturesCalled;
+}
+
 bool SchedulerStateMachine::drawSuspendedUntilCommit() const
 {
     if (!m_canDraw)
@@ -109,7 +121,19 @@ bool SchedulerStateMachine::shouldDraw() const
 
 bool SchedulerStateMachine::shouldAttemptTreeActivation() const
 {
-  return m_hasPendingTree && m_insideVSync && !hasAttemptedTreeActivationThisFrame();
+    return m_hasPendingTree && m_insideVSync && !hasAttemptedTreeActivationThisFrame();
+}
+
+bool SchedulerStateMachine::shouldCheckForCompletedTextures() const
+{
+    if (!m_settings.implSidePainting)
+        return false;
+    if (hasCheckedForCompletedTexturesThisFrame())
+        return false;
+
+    return shouldAttemptTreeActivation() ||
+           shouldDraw() ||
+           m_swapUsedIncompleteTexture;
 }
 
 bool SchedulerStateMachine::shouldAcquireLayerTexturesForMainThread() const
@@ -144,6 +168,8 @@ SchedulerStateMachine::Action SchedulerStateMachine::nextAction() const
             return ACTION_BEGIN_OUTPUT_SURFACE_RECREATION;
         if (m_outputSurfaceState == OUTPUT_SURFACE_RECREATING)
             return ACTION_NONE;
+        if (shouldCheckForCompletedTextures())
+            return ACTION_CHECK_FOR_NEW_TEXTURES;
         if (shouldAttemptTreeActivation())
             return ACTION_ACTIVATE_PENDING_TREE_IF_NEEDED;
         if (shouldDraw())
@@ -154,6 +180,8 @@ SchedulerStateMachine::Action SchedulerStateMachine::nextAction() const
         return ACTION_NONE;
 
     case COMMIT_STATE_FRAME_IN_PROGRESS:
+        if (shouldCheckForCompletedTextures())
+            return ACTION_CHECK_FOR_NEW_TEXTURES;
         if (shouldAttemptTreeActivation())
             return ACTION_ACTIVATE_PENDING_TREE_IF_NEEDED;
         if (shouldDraw())
@@ -164,6 +192,8 @@ SchedulerStateMachine::Action SchedulerStateMachine::nextAction() const
         return ACTION_COMMIT;
 
     case COMMIT_STATE_WAITING_FOR_FIRST_DRAW: {
+        if (shouldCheckForCompletedTextures())
+            return ACTION_CHECK_FOR_NEW_TEXTURES;
         if (shouldAttemptTreeActivation())
             return ACTION_ACTIVATE_PENDING_TREE_IF_NEEDED;
         if (shouldDraw() || m_outputSurfaceState == OUTPUT_SURFACE_LOST)
@@ -177,6 +207,8 @@ SchedulerStateMachine::Action SchedulerStateMachine::nextAction() const
     }
 
     case COMMIT_STATE_WAITING_FOR_FIRST_FORCED_DRAW:
+        if (shouldCheckForCompletedTextures())
+            return ACTION_CHECK_FOR_NEW_TEXTURES;
         if (shouldAttemptTreeActivation())
             return ACTION_ACTIVATE_PENDING_TREE_IF_NEEDED;
         if (m_needsForcedRedraw)
@@ -193,6 +225,10 @@ void SchedulerStateMachine::updateState(Action action)
     case ACTION_NONE:
         return;
 
+    case ACTION_CHECK_FOR_NEW_TEXTURES:
+        m_lastFrameNumberWhereCheckForCompletedTexturesCalled = m_currentFrameNumber;
+        return;
+
     case ACTION_ACTIVATE_PENDING_TREE_IF_NEEDED:
         m_lastFrameNumberWhereTreeActivationAttempted = m_currentFrameNumber;
         return;
@@ -277,6 +313,9 @@ bool SchedulerStateMachine::vsyncCallbackNeeded() const
     if (m_needsForcedRedraw)
         return true;
 
+    if (m_visible && m_swapUsedIncompleteTexture)
+        return true;
+
     return m_needsRedraw && m_visible && m_outputSurfaceState == OUTPUT_SURFACE_ACTIVE;
 }
 
@@ -301,6 +340,11 @@ void SchedulerStateMachine::setNeedsRedraw()
     m_needsRedraw = true;
 }
 
+void SchedulerStateMachine::didSwapUseIncompleteTexture()
+{
+    m_swapUsedIncompleteTexture = true;
+}
+
 void SchedulerStateMachine::setNeedsForcedRedraw()
 {
     m_needsForcedRedraw = true;