resolution support fix/improvement
    * adding compatibility menu
    * backup gravity
    * set expanable=true if the screen size is hvga * density.
    * added "supports any density" mode. I'll add sdk check later.
    * disallow to catch orientation change event if the app is not expandable. This
      was causing layout problem under non-expandable mode. I discussed this with Mike C
      and we agreed to do this approach for now. We'll revisit if this causes problem to
      a lot of applications.
diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index 52cec22..c2da593 100644
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -1025,6 +1025,14 @@
         public static final String SCREEN_OFF_TIMEOUT = "screen_off_timeout";
 
         /**
+         * If 0, the compatibility mode is off for all applications.
+         * If 1, older applications run under compatibility mode.
+         * TODO: remove this settings before code freeze (bug/1907571)
+         * @hide
+         */
+        public static final String COMPATIBILITY_MODE = "compatibility_mode";
+
+        /**
          * The screen backlight brightness between 0 and 255.
          */
         public static final String SCREEN_BRIGHTNESS = "screen_brightness";