Shared Raster Worker Threads

cc/resources/raster_worker_pool.h

Index: cc/resources/raster_worker_pool.h
diff --git a/cc/resources/raster_worker_pool.h b/cc/resources/raster_worker_pool.h
index 07d47d796588e7e78ae2064f4655477fa354b8b3..b25be8c13a6f30012f6ccd5958705ec5e4280b2b 100644
--- a/cc/resources/raster_worker_pool.h
+++ b/cc/resources/raster_worker_pool.h
@@ -192,6 +192,11 @@ class CC_EXPORT RasterWorkerPool : public WorkerPool {
   // Returns the format that needs to be used for raster task resources.
   virtual ResourceFormat GetResourceFormat() const = 0;
 
+  // Sets the number of threads to use for running raster tasks.
+  // Can only be called once prior to GetNumRasterThreads().
+  // Caller is responsible for correct ordering.
+  static void SetNumRasterThreads(int num_threads);
+
   // Force a check for completed raster tasks.
   // Calls completion callbacks on completed tasks.
   virtual void CheckForCompletedTasks();
@@ -230,8 +235,7 @@ class CC_EXPORT RasterWorkerPool : public WorkerPool {
                          scoped_refptr<internal::WorkerPoolTask> > TaskMap;
 
   RasterWorkerPool(ResourceProvider* resource_provider,
-                   ContextProvider* context_provider,
-                   size_t num_threads);
+                   ContextProvider* context_provider);
 
   virtual void OnRasterTasksFinished() = 0;
   virtual void OnRasterTasksRequiredForActivationFinished() = 0;