Gamepad: make gamepad events play well with page visibility

Source/platform/AsyncMethodRunner.h

Index: Source/platform/AsyncMethodRunner.h
diff --git a/Source/platform/AsyncMethodRunner.h b/Source/platform/AsyncMethodRunner.h
index 6b006714d51afb69e4b2bdd57dd93a349505bb16..c19857b5e68bf911587d37919e57f3433940c35c 100644
--- a/Source/platform/AsyncMethodRunner.h
+++ b/Source/platform/AsyncMethodRunner.h
@@ -74,7 +74,8 @@ public:
     // ActiveDOMObject::suspend().
     void suspend()
     {
-        ASSERT(!m_suspended);
+        if (m_suspended)
+            return;

[kbalazs, 2014/07/08 21:01:20]

FYI I have added this to avoid special casing the first pageBecomeVisible that
comes when the view is set up initially.

         m_suspended = true;
 
         if (!m_timer.isActive())
@@ -87,7 +88,8 @@ public:
     // Resumes pending method run.
     void resume()
     {
-        ASSERT(m_suspended);
+        if (!m_suspended)
+            return;
         m_suspended = false;
 
         if (!m_runWhenResumed)