Prevent repeated VRDisplay.requestPresent calls from spamming the device

third_party/WebKit/Source/modules/vr/VRDisplay.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef VRDisplay_h
 #define VRDisplay_h
 
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "core/dom/Document.h"
 #include "core/dom/FrameRequestCallback.h"
@@ skipping 76 matching lines @@
   friend class VRController;
 
   VRDisplay(NavigatorVR*,
             device::mojom::blink::VRDisplayPtr,
             device::mojom::blink::VRDisplayClientRequest);
 
   void update(const device::mojom::blink::VRDisplayInfoPtr&);
 
   void updatePose();
 
-  void beginPresent(ScriptPromiseResolver*);
+  void beginPresent();
   void forceExitPresent();
 
   void updateLayerBounds();
   void disconnected();
 
   VRController* controller();
 
  private:
   void onFullscreenCheck(TimerBase*);
-  void onPresentComplete(ScriptPromiseResolver*, bool);
+  void onPresentComplete(bool);
 
   void onConnected();
   void onDisconnected();
 
   void OnPresentChange();
 
   // VRDisplayClient
   void OnChanged(device::mojom::blink::VRDisplayInfoPtr) override;
   void OnExitPresent() override;
   void OnBlur() override;
@@ skipping 29 matching lines @@
 
   Member<ScriptedAnimationController> m_scriptedAnimationController;
   bool m_animationCallbackRequested;
   bool m_inAnimationFrame;
   bool m_displayBlurred;
   bool m_reenteredFullscreen;
 
   device::mojom::blink::VRDisplayPtr m_display;
 
   mojo::Binding<device::mojom::blink::VRDisplayClient> m_binding;
+
+  HeapDeque<Member<ScriptPromiseResolver>> m_pendingPresentResolvers;
 };
 
 using VRDisplayVector = HeapVector<Member<VRDisplay>>;
 
 enum class PresentationResult {
   Requested = 0,
   Success = 1,
   SuccessAlreadyPresenting = 2,
   VRDisplayCannotPresent = 3,
   PresentationNotSupportedByDisplay = 4,
   VRDisplayNotFound = 5,
   NotInitiatedByUserGesture = 6,
   InvalidNumberOfLayers = 7,
   InvalidLayerSource = 8,
   LayerSourceMissingWebGLContext = 9,
   InvalidLayerBounds = 10,
   ServiceInactive = 11,
   RequestDenied = 12,
   PresentationResultMax,  // Must be last member of enum.
 };
 
 void ReportPresentationResult(PresentationResult);
 
 }  // namespace blink
 
 #endif  // VRDisplay_h