Initialize TaskScheduler in renderers.

content/public/renderer/content_renderer_client.h

Index: content/public/renderer/content_renderer_client.h
diff --git a/content/public/renderer/content_renderer_client.h b/content/public/renderer/content_renderer_client.h
index 5e62b3a451a3a8c8b184daa436fc14c56a5ee342..940d7c7812d31042999715bef490d63b0cf7d0d2 100644
--- a/content/public/renderer/content_renderer_client.h
+++ b/content/public/renderer/content_renderer_client.h
@@ -13,6 +13,7 @@
 #include <vector>
 
 #include "base/bind.h"
+#include "base/callback_forward.h"
 #include "base/memory/ref_counted.h"
 #include "base/strings/string16.h"
 #include "build/build_config.h"
@@ -28,7 +29,9 @@ class SkBitmap;
 
 namespace base {
 class FilePath;
+class SchedulerWorkerPoolParams;
 class SingleThreadTaskRunner;
+class TaskTraits;
 }
 
 namespace blink {
@@ -136,6 +139,19 @@ class CONTENT_EXPORT ContentRendererClient {
   virtual bool ShouldSuppressErrorPage(RenderFrame* render_frame,
                                        const GURL& url);
 
+  // Returns true if the renderer should initialize a TaskScheduler. If so,
+  // |worker_pool_params_vector| is filled with parameters describing the worker
+  // pools to create, |worker_pool_index_for_traits_callback| is set to a
+  // callback that returns the index in |worker_pools_params_vector| of the
+  // worker pool in which a task with given traits should run and
+  // |should_redirect_sequenced_worker_pool| indicates whether
+  // SequencedWorkerPools should be redirected to TaskScheduler.
+  virtual bool ShouldInitializeTaskScheduler(
+      std::vector<base::SchedulerWorkerPoolParams>* worker_pool_params_vector,
+      base::Callback<size_t(const base::TaskTraits& traits)>*
+          worker_pool_index_for_traits_callback,
+      bool* should_redirect_sequenced_worker_pool);
+
   // Returns the information to display when a navigation error occurs.
   // If |error_html| is not null then it may be set to a HTML page containing
   // the details of the error and maybe links to more info.