Use AlertDialog for MediaRouteControllerDialog

Bug: 19876497, Bug: 21795195, Bug: 22044600
Change-Id: I8ec3b17d026b2690edad4b5c4d61741e29b653db
diff --git a/core/java/com/android/internal/app/MediaRouteControllerDialog.java b/core/java/com/android/internal/app/MediaRouteControllerDialog.java
index b0e0373..4a468be 100644
--- a/core/java/com/android/internal/app/MediaRouteControllerDialog.java
+++ b/core/java/com/android/internal/app/MediaRouteControllerDialog.java
@@ -18,7 +18,7 @@
 
 import com.android.internal.R;
 
-import android.app.Dialog;
+import android.app.AlertDialog;
 import android.app.MediaRouteActionProvider;
 import android.app.MediaRouteButton;
 import android.content.Context;
@@ -46,7 +46,7 @@
  *
  * TODO: Move this back into the API, as in the support library media router.
  */
-public class MediaRouteControllerDialog extends Dialog {
+public class MediaRouteControllerDialog extends AlertDialog {
     // Time to wait before updating the volume when the user lets go of the seek bar
     // to allow the route provider time to propagate the change and publish a new
     // route descriptor.
@@ -134,8 +134,6 @@
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
 
-        getWindow().requestFeature(Window.FEATURE_LEFT_ICON);
-
         setContentView(R.layout.media_route_controller_dialog);
 
         mVolumeLayout = (LinearLayout)findViewById(R.id.media_route_volume_layout);