Deprecate WebThread::getWebTaskRunner.

third_party/WebKit/public/platform/WebThread.h

Index: third_party/WebKit/public/platform/WebThread.h
diff --git a/third_party/WebKit/public/platform/WebThread.h b/third_party/WebKit/public/platform/WebThread.h
index 0fc11bf1ebaa735ca6a2709af062e7cb0ec65594..3e61cf23da87d19e93206d743dfb39da5d3951f8 100644
--- a/third_party/WebKit/public/platform/WebThread.h
+++ b/third_party/WebKit/public/platform/WebThread.h
@@ -65,8 +65,12 @@ class BLINK_PLATFORM_EXPORT WebThread {
     virtual void didProcessTask() = 0;
   };
 
-  // Returns a WebTaskRunner bound to the underlying scheduler's default task
-  // queue.
+  // DEPRECATED: Returns a WebTaskRunner bound to the underlying scheduler's
+  // default task queue.
+  //
+  // Default scheduler task queue does not give scheduler enough freedom to
+  // manage task priorities and should not be used.
+  // Use TaskRunnerHelper::get instead (crbug.com/624696).
   virtual WebTaskRunner* getWebTaskRunner() { return nullptr; }
   base::SingleThreadTaskRunner* getSingleThreadTaskRunner();