Add controllers for iinstant app related preferences.

For AppInfoDashboardFragment:
- add app installer preference into the preference screen
instead of creating it dynamically.
- add controller for the App Installer, Instant App buttons, and instant
app domains preferences.

Bug: 69384089
Test: make RunSettingsRoboTests
Change-Id: I8d362cacb78077c173130018c33c4d00abfe9843

src/com/android/settings/applications/instantapps/InstantAppButtonsController.java

@@ -21,7 +21,6 @@ import android.app.Fragment;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.Intent;
-import android.content.pm.PackageManager;
 import android.os.UserHandle;
 import android.view.View;
 import android.widget.Button;