cc: Remove contents_texture_manager from LayerTreeHost(Impl) and proxy.

cc/trees/thread_proxy.cc

Index: cc/trees/thread_proxy.cc
diff --git a/cc/trees/thread_proxy.cc b/cc/trees/thread_proxy.cc
index c9bd06f7d13c867ca3fb2ae4f256b5e1c9462e36..8ce9c3773463946ba6b71ee4a9093a15f273df19 100644
--- a/cc/trees/thread_proxy.cc
+++ b/cc/trees/thread_proxy.cc
@@ -97,18 +97,12 @@ ThreadProxy::MainThreadOrBlockedMainThread::MainThreadOrBlockedMainThread(
 
 ThreadProxy::MainThreadOrBlockedMainThread::~MainThreadOrBlockedMainThread() {}
 
-PrioritizedResourceManager*
-ThreadProxy::MainThreadOrBlockedMainThread::contents_texture_manager() {
-  return layer_tree_host->contents_texture_manager();
-}
-
 ThreadProxy::CompositorThreadOnly::CompositorThreadOnly(
     ThreadProxy* proxy,
     int layer_tree_host_id,
     RenderingStatsInstrumentation* rendering_stats_instrumentation,
     scoped_ptr<BeginFrameSource> external_begin_frame_source)
     : layer_tree_host_id(layer_tree_host_id),
-      contents_texture_manager(NULL),
       commit_completion_event(NULL),
       completion_event_for_commit_held_on_tree_activation(NULL),
       next_frame_is_newly_committed_frame(false),
@@ -212,22 +206,6 @@ void ThreadProxy::DidLoseOutputSurface() {
   TRACE_EVENT0("cc", "ThreadProxy::DidLoseOutputSurface");
   DCHECK(IsMainThread());
   layer_tree_host()->DidLoseOutputSurface();
-
-  {
-    DebugScopedSetMainThreadBlocked main_thread_blocked(this);
-
-    // Return lost resources to their owners immediately.
-    BlockingTaskRunner::CapturePostTasks blocked(
-        blocking_main_thread_task_runner());
-
-    CompletionEvent completion;
-    Proxy::ImplThreadTaskRunner()->PostTask(
-        FROM_HERE,
-        base::Bind(&ThreadProxy::DeleteContentsTexturesOnImplThread,
-                   impl_thread_weak_ptr_,
-                   &completion));
-    completion.Wait();
-  }
 }
 
 void ThreadProxy::RequestNewOutputSurface() {
@@ -421,32 +399,6 @@ void ThreadProxy::PostAnimationEventsToMainThreadOnImplThread(
                  base::Passed(&events)));
 }
 
-bool ThreadProxy::ReduceContentsTextureMemoryOnImplThread(size_t limit_bytes,
-                                                          int priority_cutoff) {
-  DCHECK(IsImplThread());
-
-  if (!impl().contents_texture_manager)
-    return false;
-  if (!impl().layer_tree_host_impl->resource_provider())
-    return false;
-
-  bool reduce_result =
-      impl().contents_texture_manager->ReduceMemoryOnImplThread(
-          limit_bytes,
-          priority_cutoff,
-          impl().layer_tree_host_impl->resource_provider());
-  if (!reduce_result)
-    return false;
-
-  // The texture upload queue may reference textures that were just purged,
-  // clear them from the queue.
-  if (impl().current_resource_update_controller) {
-    impl()
-        .current_resource_update_controller->DiscardUploadsToEvictedResources();
-  }
-  return true;
-}
-
 bool ThreadProxy::IsInsideDraw() { return impl().inside_draw; }
 
 void ThreadProxy::SetNeedsRedraw(const gfx::Rect& damage_rect) {
@@ -796,17 +748,6 @@ void ThreadProxy::BeginMainFrame(
   layer_tree_host()->AnimateLayers(
       begin_main_frame_state->begin_frame_args.frame_time);
 
-  // Unlink any backings that the impl thread has evicted, so that we know to
-  // re-paint them in UpdateLayers.
-  if (blocked_main().contents_texture_manager()) {
-    blocked_main().contents_texture_manager()->UnlinkAndClearEvictedBackings();
-
-    blocked_main().contents_texture_manager()->SetMaxMemoryLimitBytes(
-        begin_main_frame_state->memory_allocation_limit_bytes);
-    blocked_main().contents_texture_manager()->SetExternalPriorityCutoff(
-        begin_main_frame_state->memory_allocation_priority_cutoff);
-  }
-
   // Recreate all UI resources if there were evicted UI resources when the impl
   // thread initiated the commit.
   if (begin_main_frame_state->evicted_ui_resources)
@@ -916,28 +857,6 @@ void ThreadProxy::StartCommitOnImplThread(CompletionEvent* completion,
 
   scoped_ptr<ResourceUpdateQueue> queue(raw_queue);
 
-  if (impl().contents_texture_manager) {
-    DCHECK_EQ(impl().contents_texture_manager,
-              blocked_main().contents_texture_manager());
-  } else {
-    // Cache this pointer that was created on the main thread side to avoid a
-    // data race between creating it and using it on the compositor thread.
-    impl().contents_texture_manager = blocked_main().contents_texture_manager();
-  }
-
-  if (impl().contents_texture_manager) {
-    if (impl().contents_texture_manager->LinkedEvictedBackingsExist()) {
-      // Clear any uploads we were making to textures linked to evicted
-      // resources
-      queue->ClearUploadsToEvictedResources();
-      // Some textures in the layer tree are invalid. Kick off another commit
-      // to fill them again.
-      SetNeedsCommitOnImplThread();
-    }
-
-    impl().contents_texture_manager->PushTexturePrioritiesToBackings();
-  }
-
   impl().commit_completion_event = completion;
   impl().current_resource_update_controller = ResourceUpdateController::Create(
       this,
@@ -1213,16 +1132,6 @@ void ThreadProxy::InitializeImplOnImplThread(CompletionEvent* completion) {
   completion->Signal();
 }
 
-void ThreadProxy::DeleteContentsTexturesOnImplThread(
-    CompletionEvent* completion) {
-  TRACE_EVENT0("cc", "ThreadProxy::DeleteContentsTexturesOnImplThread");
-  DCHECK(IsImplThread());
-  DCHECK(IsMainThreadBlocked());
-  layer_tree_host()->DeleteContentsTexturesOnImplThread(
-      impl().layer_tree_host_impl->resource_provider());
-  completion->Signal();
-}
-
 void ThreadProxy::InitializeOutputSurfaceOnImplThread(
     scoped_ptr<OutputSurface> output_surface) {
   TRACE_EVENT0("cc", "ThreadProxy::InitializeOutputSurfaceOnImplThread");
@@ -1263,8 +1172,6 @@ void ThreadProxy::LayerTreeHostClosedOnImplThread(CompletionEvent* completion) {
   TRACE_EVENT0("cc", "ThreadProxy::LayerTreeHostClosedOnImplThread");
   DCHECK(IsImplThread());
   DCHECK(IsMainThreadBlocked());
-  layer_tree_host()->DeleteContentsTexturesOnImplThread(
-      impl().layer_tree_host_impl->resource_provider());
   impl().current_resource_update_controller = nullptr;
   impl().scheduler = nullptr;
   impl().layer_tree_host_impl = nullptr;
@@ -1273,7 +1180,6 @@ void ThreadProxy::LayerTreeHostClosedOnImplThread(CompletionEvent* completion) {
   // holding while still on the compositor thread. This also ensures any
   // callbacks holding a ThreadProxy pointer are cancelled.
   impl().smoothness_priority_expiration_notifier.Shutdown();
-  impl().contents_texture_manager = NULL;
   completion->Signal();
 }
 
@@ -1339,10 +1245,9 @@ void ThreadProxy::RenewTreePriority() {
   if (impl().smoothness_priority_expiration_notifier.HasPendingNotification())
     priority = SMOOTHNESS_TAKES_PRIORITY;
 
-  // New content always takes priority when the active tree has
-  // evicted resources or there is an invalid viewport size.
-  if (impl().layer_tree_host_impl->active_tree()->ContentsTexturesPurged() ||
-      impl().layer_tree_host_impl->active_tree()->ViewportSizeInvalid() ||
+  // New content always takes priority when there is an invalid viewport size or
+  // ui resources have been evicted.
+  if (impl().layer_tree_host_impl->active_tree()->ViewportSizeInvalid() ||
       impl().layer_tree_host_impl->EvictedUIResourcesExist() ||
       impl().input_throttled_until_commit) {
     // Once we enter NEW_CONTENTS_TAKES_PRIORITY mode, visible tiles on active