Pause/resume other windows when entering/exiting immersive mode

app/src/common/shared/org/mozilla/vrbrowser/VRBrowserActivity.java

@@ -799,6 +799,7 @@ void pauseGeckoViewCompositor() {
             return;
         }
         mIsPresentingImmersive = true;
+        mWindows.enterImmersiveMode();
         TelemetryWrapper.startImmersive();
         PauseCompositorRunnable runnable = new PauseCompositorRunnable();
 
@@ -821,6 +822,7 @@ void resumeGeckoViewCompositor() {
             return;
         }
         mIsPresentingImmersive = false;
+        mWindows.exitImmersiveMode();
         // Show the window in front of you when you exit immersive mode.
         resetUIYaw();
 

app/src/common/shared/org/mozilla/vrbrowser/ui/widgets/Windows.java

@@ -70,6 +70,7 @@ class WindowsState {
     private WindowPlacement mPrevWindowPlacement;
     private boolean mStoredCurvedMode = false;
     private boolean mForcedCurvedMode = false;
+    private boolean mIsPaused = false;
 
     public enum WindowPlacement{
         FRONT(0),
@@ -363,6 +364,8 @@ public void resumeCompositor() {
     }
 
     public void onPause() {
+        mIsPaused = true;
+
         saveState();
         for (WindowWidget window: mRegularWindows) {
             window.onPause();
@@ -373,6 +376,8 @@ public void onPause() {
     }
 
     public void onResume() {
+        mIsPaused = false;
+
         for (WindowWidget window: mRegularWindows) {
             window.onResume();
         }
@@ -395,6 +400,43 @@ public boolean isInPrivateMode() {
         return mPrivateMode;
     }
 
+    public void enterImmersiveMode() {
+        if (!isInPrivateMode()) {
+            for (WindowWidget window: mRegularWindows) {
+                if (window != mFocusedWindow) {
+                    window.onPause();
+                }
+            }
+
+        } else {
+            for (WindowWidget window: mPrivateWindows) {
+                if (window != mFocusedWindow) {
+                    window.onPause();
+                }
+            }
+        }
+    }
+
+    public void exitImmersiveMode() {
+        if (mIsPaused) {
+            return;
+        }
+
+        if (!isInPrivateMode()) {
+            for (WindowWidget window: mRegularWindows) {
+                if (window != mFocusedWindow) {
+                    window.onResume();
+                }
+            }
+
+        } else {
+            for (WindowWidget window: mPrivateWindows) {
+                if (window != mFocusedWindow) {
+                    window.onResume();
+                }
+            }
+        }
+    }
 
     public void enterPrivateMode() {
         if (mPrivateMode) {