Bug 1501869 - Part 2: Stop calling VR tasks when they are at background. r=kip

Differential Revision: https://phabricator.services.mozilla.com/D9880

--HG--
extra : moz-landing-system : lando

dom/base/nsGlobalWindowInner.cpp

@@ -4446,6 +4446,22 @@ nsGlobalWindowInner::ResetVRTelemetry(bool aUpdate)
   }
 }
 
+void
+nsGlobalWindowInner::StartVRActivity()
+{
+  if (mVREventObserver) {
+    mVREventObserver->StartActivity();
+  }
+}
+
+void
+nsGlobalWindowInner::StopVRActivity()
+{
+  if (mVREventObserver) {
+    mVREventObserver->StopActivity();
+  }
+}
+
 #ifndef XP_WIN // This guard should match the guard at the callsite.
 static bool ShouldShowFocusRingIfFocusedByMouse(nsIContent* aNode)
 {

dom/base/nsGlobalWindowInner.h

@@ -559,6 +559,9 @@ public:
   // false for only resetting the timestamp.
   void ResetVRTelemetry(bool aUpdate);
 
+  void StartVRActivity();
+  void StopVRActivity();
+
   // Update the VR displays for this window
   bool UpdateVRDisplays(nsTArray<RefPtr<mozilla::dom::VRDisplay>>& aDisplays);
 

dom/base/nsGlobalWindowOuter.cpp

@@ -6641,6 +6641,7 @@ nsGlobalWindowOuter::SetIsBackground(bool aIsBackground)
     // the background window.
     if (inner && changed) {
       inner->StopGamepadHaptics();
+      inner->StopVRActivity();
       // true is for asking to set the delta time to
       // the telemetry.
       inner->ResetVRTelemetry(true);
@@ -6653,6 +6654,7 @@ nsGlobalWindowOuter::SetIsBackground(bool aIsBackground)
     // false is for only resetting the timestamp.
     inner->ResetVRTelemetry(false);
     inner->SyncGamepadState();
+    inner->StartVRActivity();
   }
 }
 

dom/vr/VREventObserver.cpp

@@ -26,6 +26,7 @@ VREventObserver::VREventObserver(nsGlobalWindowInner* aGlobalWindow)
   : mWindow(aGlobalWindow)
   , mIs2DView(true)
   , mHasReset(false)
+  , mStopActivity(false)
 {
   MOZ_ASSERT(aGlobalWindow);
 
@@ -55,6 +56,7 @@ VREventObserver::DisconnectFromOwner()
     VRManagerChild* vmc = VRManagerChild::Get();
     vmc->RemoveListener(this);
   }
+  mStopActivity = true;
 }
 
 void
@@ -77,6 +79,28 @@ VREventObserver::UpdateSpentTimeIn2DTelemetry(bool aUpdate)
   }
 }
 
+void
+VREventObserver::StartActivity()
+{
+  mStopActivity = false;
+  VRManagerChild* vmc = VRManagerChild::Get();
+  vmc->StartActivity();
+}
+
+void
+VREventObserver::StopActivity()
+{
+  mStopActivity = true;
+  VRManagerChild* vmc = VRManagerChild::Get();
+  vmc->StopActivity();
+}
+
+bool
+VREventObserver::GetStopActivityStatus()
+{
+  return mStopActivity;
+}
+
 void
 VREventObserver::NotifyAfterLoad()
 {

dom/vr/VREventObserver.h

@@ -33,6 +33,9 @@ public:
 
   void DisconnectFromOwner();
   void UpdateSpentTimeIn2DTelemetry(bool aUpdate);
+  void StartActivity();
+  void StopActivity();
+  bool GetStopActivityStatus();
 
 private:
   ~VREventObserver();
@@ -43,6 +46,7 @@ private:
   TimeStamp mSpendTimeIn2DView;
   bool mIs2DView;
   bool mHasReset;
+  bool mStopActivity;
 };
 
 } // namespace dom

gfx/vr/VRManager.h

@@ -33,7 +33,6 @@ class VRSystemManagerExternal;
 class VRManager
 {
   NS_INLINE_DECL_THREADSAFE_REFCOUNTING(mozilla::gfx::VRManager)
-  friend class VRManagerParent;
 
 public:
   static void ManagerInit();

gfx/vr/ipc/PVRManager.ipdl

@@ -67,6 +67,8 @@ parent:
   async NewPoseMoveToMockController(uint32_t aDeviceID, GamepadPoseState aPose);
   async StartVRNavigation(uint32_t aDeviceID);
   async StopVRNavigation(uint32_t aDeviceID, TimeDuration aDuration);
+  async StartActivity();
+  async StopActivity();
 
 child:
   // Notify children of updated VR display enumeration and details.  This will

gfx/vr/ipc/VRManagerChild.cpp

@@ -618,6 +618,25 @@ VRManagerChild::RemoveListener(dom::VREventObserver* aObserver)
   }
 }
 
+void
+VRManagerChild::StartActivity()
+{
+  Unused << SendStartActivity();
+}
+
+void
+VRManagerChild::StopActivity()
+{
+  for (auto& listener : mListeners) {
+    if (!listener->GetStopActivityStatus()) {
+      // We are still showing VR in the active window.
+      return;
+    }
+  }
+
+  Unused << SendStopActivity();
+}
+
 void
 VRManagerChild::HandleFatalError(const char* aMsg) const
 {

gfx/vr/ipc/VRManagerChild.h

@@ -42,6 +42,8 @@ public:
   void AddListener(dom::VREventObserver* aObserver);
   // Indicate that an observer should no longer receive VR events.
   void RemoveListener(dom::VREventObserver* aObserver);
+  void StartActivity();
+  void StopActivity();
 
   bool GetVRDisplays(nsTArray<RefPtr<VRDisplayClient> >& aDisplays);
   bool RefreshVRDisplaysWithCallback(uint64_t aWindowId);

gfx/vr/ipc/VRManagerParent.cpp

@@ -24,6 +24,7 @@ VRManagerParent::VRManagerParent(ProcessId aChildProcessId, bool aIsContentChild
   , mHaveEventListener(false)
   , mHaveControllerListener(false)
   , mIsContentChild(aIsContentChild)
+  , mVRActiveStatus(true)
 {
   MOZ_COUNT_CTOR(VRManagerParent);
   MOZ_ASSERT(NS_IsMainThread());
@@ -204,6 +205,10 @@ VRManagerParent::RecvSetGroupMask(const uint32_t& aDisplayID, const uint32_t& aG
 bool
 VRManagerParent::HaveEventListener()
 {
+  if (!mVRActiveStatus) {
+    return false;
+  }
+
   return mHaveEventListener;
 }
 
@@ -213,6 +218,12 @@ VRManagerParent::HaveControllerListener()
   return mHaveControllerListener;
 }
 
+bool
+VRManagerParent::GetVRActiveStatus()
+{
+  return mVRActiveStatus;
+}
+
 mozilla::ipc::IPCResult
 VRManagerParent::RecvSetHaveEventListener(const bool& aHaveEventListener)
 {
@@ -469,5 +480,19 @@ VRManagerParent::RecvStopVRNavigation(const uint32_t& aDeviceID, const TimeDurat
   return IPC_OK();
 }
 
+mozilla::ipc::IPCResult
+VRManagerParent::RecvStartActivity()
+{
+  mVRActiveStatus = true;
+  return IPC_OK();
+}
+
+mozilla::ipc::IPCResult
+VRManagerParent::RecvStopActivity()
+{
+  mVRActiveStatus = false;
+  return IPC_OK();
+}
+
 } // namespace gfx
 } // namespace mozilla

gfx/vr/ipc/VRManagerParent.h

@@ -39,6 +39,7 @@ public:
   bool IsSameProcess() const;
   bool HaveEventListener();
   bool HaveControllerListener();
+  bool GetVRActiveStatus();
   bool SendGamepadUpdate(const GamepadChangeEvent& aGamepadEvent);
   bool SendReplyGamepadVibrateHaptic(const uint32_t& aPromiseID);
 
@@ -75,6 +76,9 @@ protected:
   virtual mozilla::ipc::IPCResult RecvNewPoseMoveToMockController(const uint32_t& aDeviceID, const GamepadPoseState& pose) override;
   virtual mozilla::ipc::IPCResult RecvStartVRNavigation(const uint32_t& aDeviceID) override;
   virtual mozilla::ipc::IPCResult RecvStopVRNavigation(const uint32_t& aDeviceID, const TimeDuration& aTimeout) override;
+  virtual mozilla::ipc::IPCResult RecvStartActivity() override;
+  virtual mozilla::ipc::IPCResult RecvStopActivity() override;
+
 private:
   void RegisterWithManager();
   void UnregisterFromManager();
@@ -99,6 +103,10 @@ private:
   bool mHaveEventListener;
   bool mHaveControllerListener;
   bool mIsContentChild;
+
+  // When VR tabs are switched the background, we won't need to
+  // initialize its session in VRService thread.
+  bool mVRActiveStatus;
 };
 
 class VRManagerPromise final