VR: Enable browsing for CCT and make ui_scene_manager aware of whether we're in CCT.

chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java

Index: chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java
index 542ed6c78ab2793969a804f1b6512283bd0c0581..dd4cb8c6a5c3e554f749749f8241f297715f5cc9 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java
@@ -283,7 +283,7 @@ public class VrShellDelegate implements ApplicationStatus.ActivityStateListener,
     }
 
     private static boolean activitySupportsVrBrowsing(Activity activity) {
-        return activity instanceof ChromeTabbedActivity;
+        return activity instanceof ChromeTabbedActivity || activity instanceof CustomTabActivity;
     }
 
     /**
@@ -473,8 +473,8 @@ public class VrShellDelegate implements ApplicationStatus.ActivityStateListener,
         mActivity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
 
         addVrViews();
-        mVrShell.initializeNative(
-                mActivity.getActivityTab(), mRequestedWebVr || tentativeWebVrMode);
+        mVrShell.initializeNative(mActivity.getActivityTab(), mRequestedWebVr || tentativeWebVrMode,
+                mActivity instanceof CustomTabActivity);
         mVrShell.setWebVrModeEnabled(mRequestedWebVr || tentativeWebVrMode);
 
         // onResume needs to be called on GvrLayout after initialization to make sure DON flow work