Fixing main process initialization code

Content Provider is no longer the 1st entry point for an app.
Moving it to a custom application class instead

Bug: 301442482
Test: Verified that the startup code gets called
Flag: N/A
Change-Id: Ibedcc7bfb0294acd9252e1d6a2a1294df32524e9

src/com/android/launcher3/LauncherApplication.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2023 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;
+
+import android.app.Application;
+
+/**
+ * Main application class for Launcher
+ */
+public class LauncherApplication extends Application {
+
+    @Override
+    public void onCreate() {
+        super.onCreate();
+        MainProcessInitializer.initialize(this);
+    }
+}