Adds the Clear App dialog for Instant Apps

Adds a confirmation dialog for the user when tapping clear app.

From this dialog the user can either cancel, or confirm they
want to clear the app.

Test: make RunSettingsRoboTests

Bug: 36536695
Change-Id: Idffcf5ef318578ae2e075ea2cbb35323d41acade

src/com/android/settings/applications/PackageManagerWrapper.java

@@ -20,6 +20,7 @@ import android.content.ComponentName;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.content.pm.ApplicationInfo;
+import android.content.pm.IPackageDeleteObserver;
 import android.content.pm.PackageManager;
 import android.content.pm.ResolveInfo;
 import android.os.UserHandle;
@@ -104,4 +105,10 @@ public interface PackageManagerWrapper {
      * Calls {@code PackageManager.getPrimaryStorageCurrentVolume}
      */
     VolumeInfo getPrimaryStorageCurrentVolume();
+
+    /**
+     * Calls {@code PackageManager.deletePackageAsUser}
+     */
+    void deletePackageAsUser(String packageName, IPackageDeleteObserver observer, int flags,
+            int userId);
 }