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

AndroidManifest-common.xml

@@ -67,6 +67,7 @@
 
     <application
         android:backupAgent="com.android.launcher3.LauncherBackupAgent"
+        android:name="com.android.launcher3.LauncherApplication"
         android:fullBackupOnly="true"
         android:backupInForeground="true"
         android:fullBackupContent="@xml/backupscheme"

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);
+    }
+}

src/com/android/launcher3/LauncherProvider.java

@@ -33,7 +33,6 @@ import android.text.TextUtils;
 import android.util.Log;
 
 import com.android.launcher3.LauncherSettings.Favorites;
-import com.android.launcher3.config.FeatureFlags;
 import com.android.launcher3.model.ModelDbController;
 import com.android.launcher3.widget.LauncherWidgetHolder;
 
@@ -44,8 +43,6 @@ import java.util.function.ToIntFunction;
 public class LauncherProvider extends ContentProvider {
     private static final String TAG = "LauncherProvider";
 
-    public static final String AUTHORITY = BuildConfig.APPLICATION_ID + ".settings";
-
     /**
      * $ adb shell dumpsys activity provider com.android.launcher3
      */
@@ -60,13 +57,6 @@ public class LauncherProvider extends ContentProvider {
 
     @Override
     public boolean onCreate() {
-        if (FeatureFlags.IS_STUDIO_BUILD) {
-            Log.d(TAG, "Launcher process started");
-        }
-
-        // The content provider exists for the entire duration of the launcher main process and
-        // is the first component to get created.
-        MainProcessInitializer.initialize(getContext().getApplicationContext());
         return true;
     }