Move Launcher classes shared between tests and prod in a separate lib

This is necessary because otherwise those are included in several gradle projects. Gradle doesn't support the same files imported in different projects, and it removes them from a random one if it happens, resulting in missing symbols.

This extracts the shared files in a new target, and adds it as dep of the original target.

Test: Build launcher + execute a few tests manually with gradle + verify that Launcher.java can resolve all symbols with gradle config
Bug: 262267728
Change-Id: Ida5b25c45320d517603834112f4699e4d3344c03

src/com/android/launcher3/testing/shared/TestInformationRequest.java

@@ -1,29 +0,0 @@
-/*
- * Copyright (C) 2021 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 com.android.launcher3.testing.shared;
-
-import android.os.Parcelable;
-
-/**
- * A Request sent to TestInformationHandler can implement this interface to carry more information.
- */
-public interface TestInformationRequest extends Parcelable {
-    /**
-     * The name for handler to dispatch request.
-     */
-    String getRequestName();
-}