Refactor BaseTimer to avoid spamming the MessageLoop with orphaned tasks.

This change maintains the same API promises*, but instead of orphaning tasks when they are stopped, the BaseTimer_Helper class holds on to the task until either (1) it expires or (2) the user requests a delay that would arrive earlier than the pending task. If the user requests a longer delay than the pending task, a followup task will be posted when the pending task fires to span the remaining time.

* The one change of usage is related to threading. The threading requirements are now more strict. It is not allowed to destruct a timer on a different thread than the one used to post tasks. A thread ID DCHECK is now in place that will help catch misuse. Some existing instances are changed as part of this CL.

A side effect of this change is that the BaseTimer and DelayTimer are simplified to use features of BaseTimer_Helper (which is now called Timer).

As suggested in timer.h, I ran the disabled TimerTest tests from linux, and they pass consistently. I also added some new tests to verify correct run states.

BUG=117451,103667,119714,119750

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=128412

Reverted: http://src.chromium.org/viewvc/chrome?view=rev&revision=128506

Review URL: https://chromiumcodereview.appspot.com/9655006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@128993 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 4 insertions, 2 deletions

diff --git a/ui/aura/gestures/gesture_recognizer_unittest.cc b/ui/aura/gestures/gesture_recognizer_unittest.cc
index 7306995..c568028 100644
--- a/ui/aura/gestures/gesture_recognizer_unittest.cc
+++ b/ui/aura/gestures/gesture_recognizer_unittest.cc
@@ -246,8 +246,10 @@ class TestOneShotGestureSequenceTimer
     : public base::OneShotTimer<GestureSequence> {
  public:
   void ForceTimeout() {
-    if (delayed_task_)
-      delayed_task_->Run();
+    if (IsRunning()) {
+      user_task().Run();
+      Stop();
+    }
   }
 };