Expose RunsTasksOnCurrentThread through WebTaskRunner

third_party/WebKit/public/platform/WebTaskRunner.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef WebTaskRunner_h
 #define WebTaskRunner_h
 
 #include "WebCommon.h"
 #include "public/platform/WebTraceLocation.h"
 
@@ skipping 20 matching lines @@
     // Takes ownership of |Task|. Can be called from any thread.
     virtual void postTask(const WebTraceLocation&, Task*) = 0;
 
     // Schedule a task to be run after |delayMs| on the the associated WebThread.
     // Takes ownership of |Task|. Can be called from any thread.
     virtual void postDelayedTask(const WebTraceLocation&, Task*, double delayMs) = 0;
 
     // Returns a clone of the WebTaskRunner.
     virtual WebTaskRunner* clone() = 0;
 
+    // Returns true if the current thread is a thread on which a task may be run.
+    // Can be called from any thread.
+    virtual bool runsTasksOnCurrentThread() = 0;
+
     // ---
 
     // Headless Chrome virtualises time for determinism and performance (fast forwarding
     // of timers). To make this work some parts of blink (e.g. Timers) need to use virtual
     // time, however by default new code should use the normal non-virtual time APIs.
 
     // Returns a double which is the number of seconds since epoch (Jan 1, 1970).
     // This may represent either the real time, or a virtual time depending on
     // whether or not the WebTaskRunner is associated with a virtual time domain or a
     // real time domain.
@@ skipping 19 matching lines @@
     std::unique_ptr<WebTaskRunner> adoptClone()
     {
         return wrapUnique(clone());
     }
 #endif
 };
 
 } // namespace blink
 
 #endif // WebTaskRunner_h