Fix broken VR transitions due to ChromeTabbedActivity not being exported.

chrome/android/java/src/org/chromium/chrome/browser/ChromeTabbedActivity.java

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.chrome.browser;
 
 import android.annotation.SuppressLint;
 import android.annotation.TargetApi;
 import android.app.Activity;
 import android.app.ActivityManager;
@@ skipping 432 matching lines @@
 
         super.onPauseWithNative();
     }
 
     @Override
     public void onStopWithNative() {
         super.onStopWithNative();
 
         if (getActivityTab() != null) getActivityTab().setIsAllowedToReturnToExternalApp(false);
 
-        if (mVrShellDelegate.isVrInitialized()) {
-            mVrShellDelegate.close();
-        }
         mTabModelSelectorImpl.saveState();
         StartupMetrics.getInstance().recordHistogram(true);
         mActivityStopMetrics.onStopWithNative(this);
     }
 
     @Override
     public void onStart() {
         super.onStart();
         StartupMetrics.getInstance().updateIntent(getIntent());
     }
 
     @Override
     public void onStartWithNative() {
         super.onStartWithNative();
         // If we don't have a current tab, show the overview mode.
         if (getActivityTab() == null) mLayoutManager.showOverview(false);
 
         resetSavedInstanceState();
     }
 
     @Override
     public void onNewIntentWithNative(Intent intent) {
         try {
             TraceEvent.begin("ChromeTabbedActivity.onNewIntentWithNative");
 
             super.onNewIntentWithNative(intent);
             if (CommandLine.getInstance().hasSwitch(ContentSwitches.ENABLE_TEST_INTENTS)) {
                 handleDebugIntent(intent);
             }
-            if (!mVrShellDelegate.isInVR() && mVrShellDelegate.isVrIntent(intent)) {
-                mVrShellDelegate.enterVRIfNecessary(false);
-            }
+            if (mVrShellDelegate.isVrIntent(intent)) mVrShellDelegate.enterVRFromIntent(intent);
         } finally {
             TraceEvent.end("ChromeTabbedActivity.onNewIntentWithNative");
         }
     }
 
     @Override
     public ChromeTabCreator getTabCreator(boolean incognito) {
         TabCreator tabCreator = super.getTabCreator(incognito);
         assert tabCreator instanceof ChromeTabCreator;
         return (ChromeTabCreator) tabCreator;
@@ skipping 223 matching lines @@
             } else {
                 if (data != null && data.getBooleanExtra(
                         FirstRunActivity.RESULT_CLOSE_APP, false)) {
                     getTabModelSelector().closeAllTabs(true);
                     finish();
                 } else {
                     launchFirstRunExperience();
                 }
             }
             return true;
+        } else if (requestCode == VrShellDelegate.EXIT_VR_RESULT) {
+            mVrShellDelegate.onExitVRResult(resultCode);
+            return true;
         }
         return false;
     }
 
     @Override
     public void onAccessibilityModeChanged(boolean enabled) {
         super.onAccessibilityModeChanged(enabled);
 
         if (mLayoutManager != null) {
             mLayoutManager.setEnableAnimations(
@@ skipping 492 matching lines @@
         MultiWindowUtils.onMultiInstanceModeStarted();
 
         tab.detachAndStartReparenting(intent, null, null);
     }
 
     @Override
     public boolean handleBackPressed() {
         if (!mUIInitialized) return false;
         final Tab currentTab = getActivityTab();
 
-        if (mVrShellDelegate.exitVRIfNecessary()) return true;
+        if (mVrShellDelegate.exitVRIfNecessary(true)) return true;
 
         if (currentTab == null) {
             recordBackPressedUma("currentTab is null", BACK_PRESSED_TAB_IS_NULL);
             moveTaskToBack(true);
             return true;
         }
 
         // If we are in overview mode and not a tablet, then leave overview mode on back.
         if (mLayoutManager.overviewVisible() && !isTablet()) {
             recordBackPressedUma("Hid overview", BACK_PRESSED_EXITED_TAB_SWITCHER);
@@ skipping 457 matching lines @@
 
         ActivityManager manager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
         for (AppTask task : manager.getAppTasks()) {
             RecentTaskInfo info = DocumentUtils.getTaskInfoFromTask(task);
             if (info == null) continue;
             if (info.id == sMergedInstanceTaskId) return true;
         }
         return false;
     }
 }