Bug 1323983 part 1 - Ensure to release the pointer even if the document has been detached. r=smaug

MozReview-Commit-ID: FY5lDQBYl6U

--HG--
extra : rebase_source : 47159f623c46549b48c786b28b5c00c246288076

dom/base/nsDocument.cpp

@@ -11703,6 +11703,13 @@ nsDocument::SetPointerLock(Element* aElement, int aCursorStyle)
   nsIPresShell* shell = GetShell();
   if (!shell) {
     NS_WARNING("SetPointerLock(): No PresShell");
+    if (!aElement) {
+      // If we are unlocking pointer lock, but for some reason the doc
+      // has already detached from the presshell, just ask the event
+      // state manager to release the pointer.
+      EventStateManager::SetPointerLock(nullptr, nullptr);
+      return true;
+    }
     return false;
   }
   nsPresContext* presContext = shell->GetPresContext();
@@ -11728,7 +11735,7 @@ nsDocument::SetPointerLock(Element* aElement, int aCursorStyle)
   RefPtr<EventStateManager> esm = presContext->EventStateManager();
   esm->SetCursor(aCursorStyle, nullptr, false,
                  0.0f, 0.0f, widget, true);
-  esm->SetPointerLock(widget, aElement);
+  EventStateManager::SetPointerLock(widget, aElement);
 
   return true;
 }

dom/events/EventStateManager.cpp

@@ -268,6 +268,7 @@ bool EventStateManager::sNormalLMouseEventInProcess = false;
 EventStateManager* EventStateManager::sActiveESM = nullptr;
 nsIDocument* EventStateManager::sMouseOverDocument = nullptr;
 nsWeakFrame EventStateManager::sLastDragOverFrame = nullptr;
+LayoutDeviceIntPoint EventStateManager::sPreLockPoint = LayoutDeviceIntPoint(0, 0);
 LayoutDeviceIntPoint EventStateManager::sLastRefPoint = kInvalidRefPoint;
 CSSIntPoint EventStateManager::sLastScreenPoint = CSSIntPoint(0, 0);
 LayoutDeviceIntPoint EventStateManager::sSynthCenteringPoint = kInvalidRefPoint;
@@ -290,7 +291,6 @@ EventStateManager::DeltaAccumulator*
 EventStateManager::EventStateManager()
   : mLockCursor(0)
   , mLastFrameConsumedSetCursor(false)
-  , mPreLockPoint(0,0)
   , mCurrentTarget(nullptr)
     // init d&d gesture state machine variables
   , mGestureDownPoint(0,0)
@@ -4357,7 +4357,7 @@ EventStateManager::GetWrapperByEventID(WidgetMouseEvent* aEvent)
   return helper;
 }
 
-void
+/* static */ void
 EventStateManager::SetPointerLock(nsIWidget* aWidget,
                                   nsIContent* aElement)
 {
@@ -4375,7 +4375,7 @@ EventStateManager::SetPointerLock(nsIWidget* aWidget,
     MOZ_ASSERT(aWidget, "Locking pointer requires a widget");
 
     // Store the last known ref point so we can reposition the pointer after unlock.
-    mPreLockPoint = sLastRefPoint;
+    sPreLockPoint = sLastRefPoint;
 
     // Fire a synthetic mouse move to ensure event state is updated. We first
     // set the mouse to the center of the window, so that the mouse event
@@ -4393,13 +4393,13 @@ EventStateManager::SetPointerLock(nsIWidget* aWidget,
     // synthetic mouse event. We first reset sLastRefPoint to its
     // pre-pointerlock position, so that the synthetic mouse event reports
     // no movement.
-    sLastRefPoint = mPreLockPoint;
+    sLastRefPoint = sPreLockPoint;
     // Reset SynthCenteringPoint to invalid so that next time we start
     // locking pointer, it has its initial value.
     sSynthCenteringPoint = kInvalidRefPoint;
     if (aWidget) {
       aWidget->SynthesizeNativeMouseMove(
-        mPreLockPoint + aWidget->WidgetToScreenOffset(), nullptr);
+        sPreLockPoint + aWidget->WidgetToScreenOffset(), nullptr);
     }
 
     // Unsuppress DnD

dom/events/EventStateManager.h

@@ -921,7 +921,7 @@ private:
   // Last mouse event mRefPoint (the offset from the widget's origin in
   // device pixels) when mouse was locked, used to restore mouse position
   // after unlocking.
-  LayoutDeviceIntPoint mPreLockPoint;
+  static LayoutDeviceIntPoint sPreLockPoint;
 
   // Stores the mRefPoint of the last synthetic mouse move we dispatched
   // to re-center the mouse when we were pointer locked. If this is (-1,-1) it
@@ -1015,7 +1015,7 @@ public:
   void KillClickHoldTimer();
   void FireContextClick();
 
-  void SetPointerLock(nsIWidget* aWidget, nsIContent* aElement) ;
+  static void SetPointerLock(nsIWidget* aWidget, nsIContent* aElement) ;
   static void sClickHoldCallback ( nsITimer* aTimer, void* aESM ) ;
 };