Expose platform thread id on blink::WebThread

content/child/webthread_impl.h

Index: content/child/webthread_impl.h
diff --git a/content/child/webthread_impl.h b/content/child/webthread_impl.h
index 4c81b2579d6806fc2f2d601682ed2446a095a056..7c074db5e0dce406a8a8f933b0220083ccfd0d11 100644
--- a/content/child/webthread_impl.h
+++ b/content/child/webthread_impl.h
@@ -22,6 +22,7 @@ class CONTENT_EXPORT WebThreadBase : public blink::WebThread {
   virtual void removeTaskObserver(TaskObserver* observer);
 
   virtual bool isCurrentThread() const = 0;
+  virtual blink::PlatformThreadId threadId() const = 0;
 
  protected:
   WebThreadBase();
@@ -47,6 +48,7 @@ class CONTENT_EXPORT WebThreadImpl : public WebThreadBase {
   base::MessageLoop* message_loop() const { return thread_->message_loop(); }
 
   virtual bool isCurrentThread() const OVERRIDE;
+  virtual blink::PlatformThreadId threadId() const OVERRIDE;
 
  private:
   scoped_ptr<base::Thread> thread_;
@@ -66,7 +68,10 @@ class WebThreadImplForMessageLoop : public WebThreadBase {
 
  private:
   virtual bool isCurrentThread() const OVERRIDE;
+  virtual blink::PlatformThreadId threadId() const OVERRIDE;
+
   scoped_refptr<base::MessageLoopProxy> message_loop_;
+  blink::PlatformThreadId thread_id_;
 };
 
 } // namespace content