Remove Task inheritance from base::Timer.

base/timer.h

Index: base/timer.h
diff --git a/base/timer.h b/base/timer.h
index 4f443a2348e6b05d22cc91ff5b131938231b04c1..0df026c999538bd36e69451f8fe78572e487d00c 100644
--- a/base/timer.h
+++ b/base/timer.h
@@ -50,7 +50,6 @@
 #include "base/base_export.h"
 #include "base/location.h"
 #include "base/logging.h"
-#include "base/task.h"
 #include "base/time.h"
 
 class MessageLoop;
@@ -86,7 +85,7 @@ class BASE_EXPORT BaseTimer_Helper {
   BaseTimer_Helper() : delayed_task_(NULL) {}
 
   // We have access to the timer_ member so we can orphan this task.
-  class TimerTask : public Task {
+  class TimerTask {
    public:
     TimerTask(const tracked_objects::Location& posted_from,
               TimeDelta delay)
@@ -95,6 +94,7 @@ class BASE_EXPORT BaseTimer_Helper {
           delay_(delay) {
     }
     virtual ~TimerTask() {}
+    virtual void Run() = 0;
     tracked_objects::Location posted_from_;
     BaseTimer_Helper* timer_;
     TimeDelta delay_;
@@ -170,7 +170,7 @@ class BaseTimer : public BaseTimer_Helper {
         ResetBaseTimer();
       else
         ClearBaseTimer();
-      DispatchToMethod(receiver_, method_, Tuple0());
+      (receiver_->*method_)();
     }
 
     TimerTask* Clone() const {