Move FrameLoader completion check timer to loading task runner.

third_party/WebKit/Source/platform/Timer.h

Index: third_party/WebKit/Source/platform/Timer.h
diff --git a/third_party/WebKit/Source/platform/Timer.h b/third_party/WebKit/Source/platform/Timer.h
index 0a9503f9e72360f70b0496b8b135b01f46b5a61b..8245b3adbf1a499f5fbfa49ee5816444badc9fcf 100644
--- a/third_party/WebKit/Source/platform/Timer.h
+++ b/third_party/WebKit/Source/platform/Timer.h
@@ -159,11 +159,18 @@ class Timer : public TimerBase {
 public:
     using TimerFiredFunction = void (TimerFiredClass::*)(Timer<TimerFiredClass>*);
 
+    // TODO(dcheng): Consider removing this overload once all timers are using the
+    // appropriate task runner. https://crbug.com/624694
     Timer(TimerFiredClass* o, TimerFiredFunction f)
         : m_object(o), m_function(f)
     {
     }
 
+    Timer(TimerFiredClass* o, TimerFiredFunction f, WebTaskRunner* webTaskRunner)
+        : TimerBase(webTaskRunner), m_object(o), m_function(f)
+    {
+    }
+
     ~Timer() override { }
 
 protected:
@@ -181,11 +188,6 @@ protected:
         return TimerIsObjectAliveTrait<TimerFiredClass>::isHeapObjectAlive(m_object);
     }
 
-    Timer(TimerFiredClass* o, TimerFiredFunction f, WebTaskRunner* webTaskRunner)
-        : TimerBase(webTaskRunner), m_object(o), m_function(f)
-    {
-    }
-
 private:
     // FIXME: Oilpan: TimerBase should be moved to the heap and m_object should be traced.
     // This raw pointer is safe as long as Timer<X> is held by the X itself (That's the case