Remove IApplicationToken

It doesn't expose any function for a long time. So it can be a
simple private inner class only for referencing ActivityRecord.

Bug: 163976519
Test: CtsActivityManagerDeviceTestCases
Change-Id: Id773ac3f0afea198ad4f8b4594d7a4cf0ad98ea8

core/java/android/view/IApplicationToken.aidl

@@ -1,25 +0,0 @@
-/* //device/java/android/android/view/IApplicationToken.aidl
-**
-** Copyright 2007, The Android Open Source Project
-**
-** Licensed under the Apache License, Version 2.0 (the "License"); 
-** you may not use this file except in compliance with the License. 
-** You may obtain a copy of the License at 
-**
-**     http://www.apache.org/licenses/LICENSE-2.0 
-**
-** Unless required by applicable law or agreed to in writing, software 
-** distributed under the License is distributed on an "AS IS" BASIS, 
-** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
-** See the License for the specific language governing permissions and 
-** limitations under the License.
-*/
-
-package android.view;
-
-/** {@hide} */
-interface IApplicationToken
-{
-  String getName();
-}
-

core/java/android/view/IWindowManager.aidl

@@ -34,7 +34,6 @@ import android.os.IRemoteCallback;
 import android.os.ParcelFileDescriptor;
 import android.view.DisplayCutout;
 import android.view.DisplayInfo;
-import android.view.IApplicationToken;
 import android.view.IAppTransitionAnimationSpecsFuture;
 import android.view.ICrossWindowBlurEnabledListener;
 import android.view.IDisplayWindowInsetsController;