Disable headlock when in VR videos

VR videos are meant for users to be immersed in the whole space around them. Because headlock locks users in the front of them, it needs to be disabled in VR videos. If users enabled headlock before entering VR videos, we disable it when VR videos show and reenable it when they are exited.

Fixes Igalia#1698

app/src/common/shared/com/igalia/wolvic/VRBrowserActivity.java

@@ -136,6 +136,8 @@ public class VRBrowserActivity extends PlatformActivity implements WidgetManager
     public static final String EXTRA_LAUNCH_IMMERSIVE_PARENT_XPATH = "launch_immersive_parent_xpath";
     public static final String EXTRA_LAUNCH_IMMERSIVE_ELEMENT_XPATH = "launch_immersive_element_xpath";
 
+    private boolean shouldRestoreHeadLockOnVRVideoExit;
+
     private BroadcastReceiver mCrashReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
@@ -2022,12 +2024,20 @@ public void onRequestPermissionsResult(int requestCode, @NonNull  String[] permi
 
     @Override
     public void showVRVideo(final int aWindowHandle, final @VideoProjectionMenuWidget.VideoProjectionFlags int aVideoProjection) {
+        if (mSettings.isHeadLockEnabled()) {
+            mSettings.setHeadLockEnabled(false);
+            shouldRestoreHeadLockOnVRVideoExit = true;
+        }
         queueRunnable(() -> showVRVideoNative(aWindowHandle, aVideoProjection));
     }
 
     @Override
     public void hideVRVideo() {
         queueRunnable(this::hideVRVideoNative);
+
+        if (shouldRestoreHeadLockOnVRVideoExit) {
+            mSettings.setHeadLockEnabled(true);
+        }
     }
 
     @Override