Pause drawing webvr when the App button is pressed

chrome/browser/android/vr_shell/ui_scene.cc

Index: chrome/browser/android/vr_shell/ui_scene.cc
diff --git a/chrome/browser/android/vr_shell/ui_scene.cc b/chrome/browser/android/vr_shell/ui_scene.cc
index 9982c988caa67049f2618b565fb6d773284eb320..b5534206c504bdc90be476abd29496c3589f5b7d 100644
--- a/chrome/browser/android/vr_shell/ui_scene.cc
+++ b/chrome/browser/android/vr_shell/ui_scene.cc
@@ -156,6 +156,10 @@ bool UiScene::GetWebVrRenderingEnabled() const {
   return webvr_rendering_enabled_;
 }
 
+void UiScene::SetWebVrRenderingEnabled(bool enabled) {
+  webvr_rendering_enabled_ = enabled;
+}
+
 const std::vector<std::unique_ptr<UiElement>>& UiScene::GetUiElements() const {
   return ui_elements_;
 }