Backing out f4ddfbf313fc (bug 905405) on a CLOSED TREE

widget/windows/nsAppShell.cpp

@@ -161,12 +161,9 @@ nsAppShell::ScheduleNativeEventCallback()
 {
   // Post a message to the hidden message window
   NS_ADDREF_THIS(); // will be released when the event is processed
-  {
-    MutexAutoLock lock(mLastNativeEventScheduledMutex);
-    // Time stamp this event so we can detect cases where the event gets
-    // dropping in sub classes / modal loops we do not control.
-    mLastNativeEventScheduled = TimeStamp::NowLoRes();
-  }
+  // Time stamp this event so we can detect cases where the event gets
+  // dropping in sub classes / modal loops we do not control. 
+  mLastNativeEventScheduled = TimeStamp::NowLoRes();
   ::PostMessage(mEventWnd, sAppShellGeckoMsgId, 0, reinterpret_cast<LPARAM>(this));
 }
 
@@ -241,13 +238,8 @@ nsAppShell::ProcessNextNativeEvent(bool mayWait)
   static const mozilla::TimeDuration nativeEventStarvationLimit =
     mozilla::TimeDuration::FromSeconds(NATIVE_EVENT_STARVATION_LIMIT);
 
-  TimeDuration timeSinceLastNativeEventScheduled;
-  {
-    MutexAutoLock lock(mLastNativeEventScheduledMutex);
-    timeSinceLastNativeEventScheduled =
-        TimeStamp::NowLoRes() - mLastNativeEventScheduled;
-  }
-  if (timeSinceLastNativeEventScheduled > nativeEventStarvationLimit) {
+  if ((TimeStamp::NowLoRes() - mLastNativeEventScheduled) >
+      nativeEventStarvationLimit) {
     ScheduleNativeEventCallback();
   }
   

widget/windows/nsAppShell.h

@@ -9,7 +9,6 @@
 #include "nsBaseAppShell.h"
 #include <windows.h>
 #include "mozilla/TimeStamp.h"
-#include "mozilla/Mutex.h"
 
 // The maximum time we allow before forcing a native event callback.
 // In seconds.
@@ -23,8 +22,7 @@ class nsAppShell : public nsBaseAppShell
 public:
   nsAppShell() :
     mEventWnd(NULL),
-    mNativeCallbackPending(false),
-    mLastNativeEventScheduledMutex("nsAppShell::mLastNativeEventScheduledMutex")
+    mNativeCallbackPending(false)
   {}
   typedef mozilla::TimeStamp TimeStamp;
 
@@ -45,8 +43,6 @@ protected:
 protected:
   HWND mEventWnd;
   bool mNativeCallbackPending;
-
-  Mutex mLastNativeEventScheduledMutex;
   TimeStamp mLastNativeEventScheduled;
 };