[vr] Bail on unhandled code points.

chrome/browser/android/vr_shell/vr_shell.cc

Index: chrome/browser/android/vr_shell/vr_shell.cc
diff --git a/chrome/browser/android/vr_shell/vr_shell.cc b/chrome/browser/android/vr_shell/vr_shell.cc
index 5a7be6589489881e3cbf47642b854a59b9b20a83..186b3b21dcda2c2c06ade0522deb6ac6b47d4393 100644
--- a/chrome/browser/android/vr_shell/vr_shell.cc
+++ b/chrome/browser/android/vr_shell/vr_shell.cc
@@ -582,12 +582,14 @@ void VrShell::ExitFullscreen() {
   }
 }
 
-void VrShell::ExitVrDueToUnsupportedMode() {
+void VrShell::ExitVrDueToUnsupportedMode(UiUnsupportedMode mode) {
   ui_->SetIsExiting();
   main_thread_task_runner_->PostDelayedTask(
       FROM_HERE,
       base::Bind(&VrShell::ForceExitVr, weak_ptr_factory_.GetWeakPtr()),
       kExitVrDueToUnsupportedModeDelay);
+  UMA_HISTOGRAM_ENUMERATION("VR.Shell.EncounteredUnsupportedMode", mode,
+                            UiUnsupportedMode::kCount);
 }
 
 void VrShell::OnVRVsyncProviderRequest(