[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 083ee3c29e097dedc1ac5986b941fee8e6fc6efd..8b80bc3661242a3ad2e0ddb283c265e9c50fea28 100644
--- a/chrome/browser/android/vr_shell/vr_shell.cc
+++ b/chrome/browser/android/vr_shell/vr_shell.cc
@@ -86,6 +86,9 @@ void SetIsInVR(content::WebContents* contents, bool is_in_vr) {
   }
 }
 
+static const char* kUnsupportedModeHistogramName =
+    "VR.Shell.EncounteredUnsupportedMode";
+
 }  // namespace
 
 VrShell::VrShell(JNIEnv* env,
@@ -581,12 +584,14 @@ 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(kUnsupportedModeHistogramName, mode,
+                            UiUnsupportedMode::kMax);
 }
 
 void VrShell::OnVRVsyncProviderRequest(