cc: Check for completed raster tasks at interval.

cc/worker_pool.h

Index: cc/worker_pool.h
diff --git a/cc/worker_pool.h b/cc/worker_pool.h
index f47dd70b9981b23af18184c6c3f0ea911b051c12..86ea529cf3ff7553e29d44c74657ca8a82aa5f8f 100644
--- a/cc/worker_pool.h
+++ b/cc/worker_pool.h
@@ -10,7 +10,6 @@
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/memory/weak_ptr.h"
 #include "base/threading/thread.h"
 #include "cc/rendering_stats.h"
 #include "cc/scoped_ptr_deque.h"
@@ -24,12 +23,16 @@ class WorkerPoolTask {
 
   virtual void Run(RenderingStats* rendering_stats) = 0;
 
+  bool IsPending();
   void Completed();
 
  protected:
   WorkerPoolTask(const base::Closure& reply);
 
   base::Closure reply_;
+
+  // Accessed from multiple threads. Set to 1 when task has completed.
+  base::subtle::Atomic32 completed_;
 };
 
 }  // namespace internal
@@ -54,9 +57,8 @@ class WorkerPool {
   // is posted to the thread that called PostTaskAndReply().
   void PostTaskAndReply(const Callback& task, const base::Closure& reply);
 
-  // Returns true when worker pool has reached its internal limit for number
-  // of pending tasks.
-  bool IsBusy();
+  // Check for completed tasks and run reply callbacks.
+  void CheckForCompletedTasks();
 
   // Toggle rendering stats collection.
   void SetRecordRenderingStats(bool record_rendering_stats);
@@ -76,6 +78,9 @@ class WorkerPool {
     // Posts a task to the worker thread.
     void PostTask(scoped_ptr<internal::WorkerPoolTask> task);
 
+    // Check for completed tasks and run reply callbacks.
+    void CheckForCompletedTasks();
+
     int num_pending_tasks() const { return pending_tasks_.size(); }
     void set_record_rendering_stats(bool record_rendering_stats) {
       record_rendering_stats_ = record_rendering_stats;
@@ -94,7 +99,6 @@ class WorkerPool {
     void OnTaskCompleted();
 
     WorkerPool* worker_pool_;
-    base::WeakPtrFactory<Worker> weak_ptr_factory_;
     ScopedPtrDeque<internal::WorkerPoolTask> pending_tasks_;
     scoped_ptr<RenderingStats> rendering_stats_;
     bool record_rendering_stats_;