Prepare chromium for WorkerThread migration to 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..476445284c8938972c4e1fc0558262737a8abb1f 100644
--- a/content/child/webthread_impl.h
+++ b/content/child/webthread_impl.h
@@ -9,6 +9,7 @@
 
 #include "base/memory/scoped_ptr.h"
 #include "base/threading/thread.h"
+#include "base/timer/timer.h"
 #include "content/common/content_export.h"
 #include "third_party/WebKit/public/platform/WebThread.h"
 
@@ -23,6 +24,11 @@ class CONTENT_EXPORT WebThreadBase : public blink::WebThread {
 
   virtual bool isCurrentThread() const = 0;
 
+  typedef void (*SharedTimerFunction)();
+  virtual void setSharedTimerFiredFunction(SharedTimerFunction timerFunction) {}
+  virtual void setSharedTimerFireInterval(double) {}
+  virtual void stopSharedTimer() {}
+
  protected:
   WebThreadBase();
 
@@ -48,7 +54,19 @@ class CONTENT_EXPORT WebThreadImpl : public WebThreadBase {
 
   virtual bool isCurrentThread() const OVERRIDE;
 
+  virtual void setSharedTimerFiredFunction(
+      SharedTimerFunction timerFunction) OVERRIDE;
+  virtual void setSharedTimerFireInterval(double interval_seconds) OVERRIDE;
+  virtual void stopSharedTimer() OVERRIDE;
+
  private:
+  void OnTimeout() {
+    if (shared_timer_function_)
+      shared_timer_function_();
+  }
+  base::OneShotTimer<WebThreadImpl> shared_timer_;
+  SharedTimerFunction shared_timer_function_;
+
   scoped_ptr<base::Thread> thread_;
 };