(not for review yet)

cc/trees/layer_tree_host.cc

 // Copyright 2011 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.
 
 #include "cc/trees/layer_tree_host.h"
 
 #include <algorithm>
 #include <stack>
 
 #include "base/bind.h"
@@ skipping 43 matching lines @@
       allow_partial_texture_updates(false),
       using_offscreen_context3d(false),
       max_texture_size(0),
       avoid_pow2_textures(false),
       using_map_image(false),
       using_shared_memory_resources(false) {}
 
 RendererCapabilities::~RendererCapabilities() {}
 
 UIResourceRequest::UIResourceRequest()
-    : type(UIResourceInvalidRequest), id(0), bitmap(NULL) {}
+    : type(UIResourceInvalidRequest), id(0), bitmap(NULL), ack(0) {}
 
 UIResourceRequest::~UIResourceRequest() {}
 
 bool LayerTreeHost::AnyLayerTreeHostInstanceExists() {
   return s_num_layer_tree_instances > 0;
 }
 
 scoped_ptr<LayerTreeHost> LayerTreeHost::Create(
     LayerTreeHostClient* client,
     const LayerTreeSettings& settings,
@@ skipping 288 matching lines @@
 
   if (!ui_resource_request_queue_.empty()) {
     sync_tree->set_ui_resource_request_queue(ui_resource_request_queue_);
     ui_resource_request_queue_.clear();
     // Process any ui resource requests in the queue.  For impl-side-painting,
     // the queue is processed in LayerTreeHostImpl::ActivatePendingTree.
     if (!settings_.impl_side_painting)
       sync_tree->ProcessUIResourceRequestQueue();
   }
 
+  // If all UI resource evictions will not be acknowledged by this commit, then
+  // another commit is required.
+  if (ui_resource_eviction_count_last_acked_ !=
+      host_impl->ui_resource_eviction_count()) {
+    host_impl->SetNeedsCommit();
+  }
+
   DCHECK(!sync_tree->ViewportSizeInvalid());
 
   if (new_impl_tree_has_no_evicted_resources) {
     if (sync_tree->ContentsTexturesPurged())
       sync_tree->ResetContentsTexturesPurged();
   }
 
   if (!settings_.impl_side_painting) {
     // If we're not in impl-side painting, the tree is immediately
     // considered active.
@@ skipping 775 matching lines @@
     UIResourceId uid = iter->first;
     UIResourceRequest request;
     request.type = UIResourceRequest::UIResourceCreate;
     request.id = uid;
     request.bitmap = iter->second->GetBitmap(uid, resource_lost);
     DCHECK(request.bitmap.get());
     ui_resource_request_queue_.push_back(request);
   }
 }
 
+void LayerTreeHost::SetUIResourceEvictionCountToAck(uint64 ui_resource_eviction_count) {
+  if (ui_resource_eviction_count_last_acked_ == ui_resource_eviction_count)
+    return;
+
+  bool resource_lost = false;
+  RecreateUIResources(resource_lost);
+
+  UIResourceRequest request;
+  request.type = UIResourceRequest::UIResourceEvictionAck;
+  request.ack = ui_resource_eviction_count;
+  ui_resource_request_queue_.push_back(request);
+  ui_resource_eviction_count_last_acked_ = ui_resource_eviction_count;
+}
+
 }  // namespace cc