Refactor Vr activity into ChromeTabbedActivity.

chrome/android/java/strings/android_chrome_strings.grd

Index: chrome/android/java/strings/android_chrome_strings.grd
diff --git a/chrome/android/java/strings/android_chrome_strings.grd b/chrome/android/java/strings/android_chrome_strings.grd
index 4ab381de5624e3aa569ed52a0c259f25c73b238d..f1a3e227a79af93722e10a98b5e2537ead8c8e82 100644
--- a/chrome/android/java/strings/android_chrome_strings.grd
+++ b/chrome/android/java/strings/android_chrome_strings.grd
@@ -226,6 +226,9 @@ CHAR-LIMIT guidelines:
       <message name="IDS_PREFS_SECTION_ADVANCED" desc='Title of "Advanced" section of preferences. [CHAR-LIMIT=32]'>
         Advanced
       </message>
+      <message name="IDS_ENTER_VR" desc="Menu item for entering VR. [CHAR-LIMIT=27]">
+        &#128083;&#128083;&#128083; Enter VR &#128083;&#128083;&#128083;
+      </message>
 
       <!-- Sign-in preference -->
       <message name="IDS_SIGN_IN_TO_CHROME" desc="Title for the button to sign in to Chrome using one's Google account. [CHAR-LIMIT=27]">