Fix call buttons being incorrectly hidden.

They were hidden incorrectly when having full-screen caller photo
enabled and an outgoing call is terminated without being answered.

Change-Id: I817a1f8d37c83aabb5470ee1ed6329b79302d338

Author: maniac103

src/com/android/incallui/CallButtonPresenter.java

@@ -280,7 +280,9 @@ private void updateUi(InCallState state, Call call) {
         } else { // DISCONNECTING, NO_CALLS
             // Keep UI visible in case it was visible before, don't cause
             // unneccessary layout changes
-            isVisible = mStateBeforeDisconnect == InCallState.INCALL;
+            isVisible = mStateBeforeDisconnect != null &&
+                    !mStateBeforeDisconnect.isIncoming() &&
+                    mStateBeforeDisconnect.isConnectingOrConnected();
         }
 
         ui.setEnabled(isEnabled, isVisible);