[java-runtime, Mono.Android] Use ApplicationRegistration.Context (#9779)

Context: #9747

Calling `Android.App.Application.Context` currently reads the
`mono.MonoPackageManager.Context` field, which is set on startup by a
`ContentProvider`.  `mono.MonoPackageManager` does not exist in
NativeAOT (#9747), so let's move the field to the
`ApplicationRegistration` type, which *does* exist.

Author: jonathanpeppers

samples/NativeAOT/NativeAotRuntimeProvider.java

@@ -1,6 +1,7 @@
 package net.dot.jni.nativeaot;
 
 import android.util.Log;
+import net.dot.android.ApplicationRegistration;
 
 public class NativeAotRuntimeProvider
     extends android.content.ContentProvider
@@ -20,9 +21,12 @@ public boolean onCreate() {
     @Override
     public void attachInfo(android.content.Context context, android.content.pm.ProviderInfo info) {
         Log.d(TAG, "NativeAotRuntimeProvider.attachInfo(): calling JavaInteropRuntime.init()…");
+        if (context instanceof android.app.Application) {
+            ApplicationRegistration.Context = context;
+        }
         JavaInteropRuntime.init();
         // NOTE: only required for custom applications
-        net.dot.android.ApplicationRegistration.registerApplications();
+        ApplicationRegistration.registerApplications();
         super.attachInfo (context, info);
     }
 

src/Mono.Android/Android.App/Application.cs

@@ -14,7 +14,7 @@ public static Context Context {
 				if (_context != null)
 					return _context;
 
-				IntPtr klass = JNIEnv.FindClass ("mono/MonoPackageManager");
+				IntPtr klass = JNIEnv.FindClass ("net/dot/android/ApplicationRegistration");
 				try {
 					IntPtr field  = JNIEnv.GetStaticFieldID (klass, "Context", "Landroid/content/Context;");
 					IntPtr lref   = JNIEnv.GetStaticObjectField (klass, field);

src/Xamarin.Android.Build.Tasks/Resources/ApplicationRegistration.java

@@ -2,6 +2,8 @@
 
 public class ApplicationRegistration {
 
+	public static android.content.Context Context;
+
 	public static void registerApplications ()
 	{
 		// REGISTER_APPLICATION_AND_INSTRUMENTATION_CLASSES_HERE		

src/java-runtime/java/mono/android/MonoPackageManager.java

@@ -18,14 +18,13 @@
 import mono.android.Runtime;
 import mono.android.DebugRuntime;
 import mono.android.BuildConfig;
+import net.dot.android.ApplicationRegistration;
 
 public class MonoPackageManager {
 
 	static Object lock = new Object ();
 	static boolean initialized;
 
-	static android.content.Context Context;
-
 	public static void LoadApplication (Context context)
 	{
 		synchronized (lock) {
@@ -41,7 +40,7 @@ public static void LoadApplication (Context context)
 			}
 
 			if (context instanceof android.app.Application) {
-				Context = context;
+				ApplicationRegistration.Context = context;
 			}
 			if (!initialized) {
 				android.content.IntentFilter timezoneChangedFilter  = new android.content.IntentFilter (
@@ -129,7 +128,7 @@ public static void LoadApplication (Context context)
 						haveSplitApks
 					);
 
-				net.dot.android.ApplicationRegistration.registerApplications ();
+				ApplicationRegistration.registerApplications ();
 
 				initialized = true;
 			}

src/java-runtime/java/net/dot/android/ApplicationRegistration.java

@@ -2,6 +2,8 @@
 
 public class ApplicationRegistration {
 
+	public static android.content.Context Context;
+
 	public static void registerApplications ()
 	{
 		// REGISTER_APPLICATION_AND_INSTRUMENTATION_CLASSES_HERE