Remove sync flush

Bug: 13952590
 It was attempting to flush state changes after the canvas was
 destroyed, which caused layer updates to crash.

 Due to the removal of SetDisplayListData, the sync mode isn't able
 to do anything ever, so remove it.

Change-Id: I1e18ce288d81fd47cc6e612afda9476f75ecef2e

libs/hwui/DeferredLayerUpdater.cpp

@@ -41,6 +41,7 @@ DeferredLayerUpdater::DeferredLayerUpdater(Layer* layer, OpenGLRenderer* rendere
 
 DeferredLayerUpdater::~DeferredLayerUpdater() {
     SkSafeUnref(mColorFilter);
+    setTransform(0);
     if (mLayer) {
         mCaches.resourceCache.decrementRefcount(mLayer);
     }

libs/hwui/renderthread/CanvasContext.cpp

@@ -387,6 +387,7 @@ void CanvasContext::setup(int width, int height) {
 
 void CanvasContext::processLayerUpdates(const Vector<DeferredLayerUpdater*>* layerUpdaters,
         bool* hasFunctors) {
+    LOG_ALWAYS_FATAL_IF(!mCanvas, "Cannot process layer updates without a canvas!");
     mGlobalContext->makeCurrent(mEglSurface);
     for (size_t i = 0; i < layerUpdaters->size(); i++) {
         DeferredLayerUpdater* update = layerUpdaters->itemAt(i);

libs/hwui/renderthread/DrawFrameTask.cpp

@@ -30,7 +30,7 @@ namespace android {
 namespace uirenderer {
 namespace renderthread {
 
-DrawFrameTask::DrawFrameTask() : mContext(0), mTaskMode(MODE_INVALID), mRenderNode(0) {
+DrawFrameTask::DrawFrameTask() : mContext(0), mRenderNode(0) {
 }
 
 DrawFrameTask::~DrawFrameTask() {
@@ -69,23 +69,14 @@ void DrawFrameTask::drawFrame(RenderThread* renderThread) {
     LOG_ALWAYS_FATAL_IF(!mRenderNode.get(), "Cannot drawFrame with no render node!");
     LOG_ALWAYS_FATAL_IF(!mContext, "Cannot drawFrame with no CanvasContext!");
 
-    postAndWait(renderThread, MODE_FULL);
+    postAndWait(renderThread);
 
     // Reset the single-frame data
     mDirty.setEmpty();
     mRenderNode = 0;
 }
 
-void DrawFrameTask::flushStateChanges(RenderThread* renderThread) {
-    LOG_ALWAYS_FATAL_IF(!mContext, "Cannot drawFrame with no CanvasContext!");
-
-    postAndWait(renderThread, MODE_STATE_ONLY);
-}
-
-void DrawFrameTask::postAndWait(RenderThread* renderThread, TaskMode mode) {
-    LOG_ALWAYS_FATAL_IF(mode == MODE_INVALID, "That's not a real mode, silly!");
-
-    mTaskMode = mode;
+void DrawFrameTask::postAndWait(RenderThread* renderThread) {
     AutoMutex _lock(mLock);
     renderThread->queue(this);
     mSignal.wait(mLock);
@@ -97,11 +88,6 @@ void DrawFrameTask::run() {
     // canUnblockUiThread is temporary until WebView has a solution for syncing frame state
     bool canUnblockUiThread = syncFrameState();
 
-    if (mTaskMode == MODE_STATE_ONLY) {
-        unblockUiThread();
-        return;
-    }
-
     // Grab a copy of everything we need
     Rect dirtyCopy(mDirty);
     sp<RenderNode> renderNode = mRenderNode;
@@ -125,12 +111,9 @@ bool DrawFrameTask::syncFrameState() {
     bool hasFunctors = false;
     mContext->processLayerUpdates(&mLayers, &hasFunctors);
 
-    // If we don't have an mRenderNode this is a state flush only
-    if (mRenderNode.get()) {
-        TreeInfo info = {0};
-        mRenderNode->prepareTree(info);
-        hasFunctors |= info.hasFunctors;
-    }
+    TreeInfo info = {0};
+    mRenderNode->prepareTree(info);
+    hasFunctors |= info.hasFunctors;
 
     return !hasFunctors;
 }

libs/hwui/renderthread/DrawFrameTask.h

@@ -56,18 +56,11 @@ public:
     void setRenderNode(RenderNode* renderNode);
     void setDirty(int left, int top, int right, int bottom);
     void drawFrame(RenderThread* renderThread);
-    void flushStateChanges(RenderThread* renderThread);
 
     virtual void run();
 
 private:
-    enum TaskMode {
-        MODE_INVALID,
-        MODE_FULL,
-        MODE_STATE_ONLY,
-    };
-
-    void postAndWait(RenderThread* renderThread, TaskMode mode);
+    void postAndWait(RenderThread* renderThread);
     bool syncFrameState();
     void unblockUiThread();
     static void drawRenderNode(CanvasContext* context, RenderNode* renderNode, Rect* dirty);
@@ -80,7 +73,6 @@ private:
     /*********************************************
      *  Single frame data
      *********************************************/
-    TaskMode mTaskMode;
     sp<RenderNode> mRenderNode;
     Rect mDirty;
 

libs/hwui/renderthread/RenderProxy.cpp

@@ -75,9 +75,6 @@ CREATE_BRIDGE1(destroyContext, CanvasContext* context) {
 
 void RenderProxy::destroyContext() {
     if (mContext) {
-        // Flush any pending changes to ensure all garbage is destroyed
-        mDrawFrameTask.flushStateChanges(&mRenderThread);
-
         SETUP_TASK(destroyContext);
         args->context = mContext;
         mContext = 0;
@@ -149,10 +146,6 @@ CREATE_BRIDGE1(destroyCanvas, CanvasContext* context) {
 }
 
 void RenderProxy::destroyCanvas() {
-    // If the canvas is being destroyed we won't be drawing again anytime soon
-    // So flush any pending state changes to allow for resource cleanup.
-    mDrawFrameTask.flushStateChanges(&mRenderThread);
-
     SETUP_TASK(destroyCanvas);
     args->context = mContext;
     post(task);