Check for antenna connected on activity restart

On activity restart, check if antenna connected or not. On activity
restart we request for audio focus and update the UI with Radio text
etc. even if antenna not connected. This enables UI and disable it again
even if FM is turned off.

CRs-Fixed: 1081388
Change-Id: I0c27f4025322451447423e1f5c07da1f8db790e6

fmapp2/src/com/caf/fmradio/FMRadio.java

@@ -439,7 +439,7 @@ public class FMRadio extends Activity
    public void onRestart() {
       Log.d(LOGTAG, "FMRadio: onRestart");
       try {
-         if (null != mService) {
+         if (null != mService && isAntennaAvailable()) {
               mService.requestFocus();
          }
       } catch (Exception e) {
@@ -505,6 +505,9 @@ public class FMRadio extends Activity
 
       super.onResume();
 
+      if (!isAntennaAvailable()) {
+          return;
+      }
       // TODO: We should return on exception or continue?
       try {
           if (mService != null)