UI Resource Manager

cc/trees/layer_tree_host.h

Index: cc/trees/layer_tree_host.h
===================================================================
--- cc/trees/layer_tree_host.h	(revision 213649)
+++ cc/trees/layer_tree_host.h	(working copy)
@@ -6,6 +6,7 @@
 #define CC_TREES_LAYER_TREE_HOST_H_
 
 #include <limits>
+#include <list>
 #include <vector>
 
 #include "base/basictypes.h"
@@ -23,6 +24,7 @@
 #include "cc/input/top_controls_state.h"
 #include "cc/layers/layer_lists.h"
 #include "cc/output/output_surface.h"
+#include "cc/resources/ui_resource_bitmap.h"
 #include "cc/scheduler/rate_limiter.h"
 #include "cc/trees/layer_tree_host_client.h"
 #include "cc/trees/layer_tree_host_common.h"
@@ -81,6 +83,19 @@
   bool using_shared_memory_resources;
 };
 
+typedef int UIResourceId;
+typedef base::Callback<scoped_refptr<UIResourceBitmap>(bool resource_lost)>
+    UIResourceCallback;
+enum UIResourceRequestType {
+  UIResourceCreate,
+  UIResourceDelete
+};
+struct UIResourceRequest {
+  UIResourceRequestType type;
+  UIResourceId id;
+  scoped_refptr<UIResourceBitmap> bitmap;
+};
+
 class CC_EXPORT LayerTreeHost : NON_EXPORTED_BASE(public RateLimiterClient) {
  public:
   static scoped_ptr<LayerTreeHost> Create(
@@ -215,6 +230,8 @@
 
   void ApplyScrollAndScale(const ScrollAndScaleSet& info);
 
+  void UIResourceLost(UIResourceId id);
+
   void SetImplTransform(const gfx::Transform& transform);
   void SetLatencyInfo(const ui::LatencyInfo& latency_info);
 
@@ -252,6 +269,16 @@
 
   bool in_paint_layer_contents() const { return in_paint_layer_contents_; }
 
+  // CreateUIResource creates a resource given a bitmap.  The bitmap is
+  // generated via a callback function, which is called when initializing the
+  // resource and when the resource has been lost (due to lost context).  The
+  // parameter of the callback is a single boolean, which indicates whether the
+  // resource has been lost or not.  CreateUIResource returns an Id of the
+  // resource, which is always positive.
+  virtual UIResourceId CreateUIResource(const UIResourceCallback& bitmap_cb);
+  // Deletes a UI resource.  May safely be called more than once.
+  virtual void DeleteUIResource(UIResourceId id);
+
   bool UsingSharedMemoryResources();
   int id() const { return tree_id_; }
 
@@ -288,6 +315,18 @@
 
   bool AnimateLayersRecursive(Layer* current, base::TimeTicks time);
 
+  void DidLoseUIResources();
+
+  // UIResourceCallback is used to retrieve the the bitmap of the resource
+  // request.  The boolean parameter indicates whether the retrieval is due
+  // to lost resource (due to lost context) or not.
+  typedef base::hash_map<UIResourceId, UIResourceCallback> UIResourceClientMap;
+  UIResourceClientMap ui_resource_client_map_;
+  int ui_resource_id_;
+
+  typedef std::list<UIResourceRequest> UIResourceRequestQueue;
+  UIResourceRequestQueue ui_resource_request_queue_;
+
   void CalculateLCDTextMetricsCallback(Layer* layer);
 
   bool animating_;