[CoreCLR] Implement GC bridge

src/Mono.Android/Android.Runtime/AndroidRuntime.cs

@@ -629,7 +629,9 @@ class AndroidValueManager : JniRuntime.JniValueManager {
 
 		public override void WaitForGCBridgeProcessing ()
 		{
-			AndroidRuntimeInternal.WaitForBridgeProcessing ();
+			if (!AndroidRuntimeInternal.BridgeProcessing)
+				return;
+			RuntimeNativeMethods._monodroid_gc_wait_for_bridge_processing ();
 		}
 
 		public override IJavaPeerable? CreatePeer (

src/Mono.Android/Android.Runtime/AndroidRuntimeInternal.cs

@@ -64,9 +64,7 @@ static void MonoUnhandledException (Exception ex)
 
 		public static void WaitForBridgeProcessing ()
 		{
-			if (!BridgeProcessing)
-				return;
-			RuntimeNativeMethods._monodroid_gc_wait_for_bridge_processing ();
+			Java.Interop.JniEnvironment.Runtime.ValueManager.WaitForGCBridgeProcessing ();
 		}
 	}
 }

src/Mono.Android/Android.Runtime/RuntimeNativeMethods.cs

@@ -2,6 +2,7 @@
 using System;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
+using System.Runtime.InteropServices.Java;
 using System.Text;
 
 namespace Android.Runtime
@@ -18,7 +19,7 @@ enum TraceKind : uint
 		All     = Java | Managed | Native | Signals,
 	}
 
-	internal static class RuntimeNativeMethods
+	internal unsafe static class RuntimeNativeMethods
 	{
 		[DllImport (RuntimeConstants.InternalDllName, CallingConvention = CallingConvention.Cdecl)]
 		internal extern static void monodroid_log (LogLevel level, LogCategories category, string message);
@@ -92,6 +93,11 @@ internal static class RuntimeNativeMethods
 		[DllImport (RuntimeConstants.InternalDllName, CallingConvention = CallingConvention.Cdecl)]
 		internal static extern bool clr_typemap_java_to_managed (string java_type_name, out IntPtr managed_assembly_name, out uint managed_type_token_id);
 
+		[DllImport (RuntimeConstants.InternalDllName, CallingConvention = CallingConvention.Cdecl)]
+		internal static extern delegate* unmanaged<MarkCrossReferencesArgs*, void> clr_initialize_gc_bridge (
+			delegate* unmanaged<MarkCrossReferencesArgs*, void> bridge_processing_started_callback,
+			delegate* unmanaged<MarkCrossReferencesArgs*, void> bridge_processing_finished_callback);
+
 		[MethodImplAttribute(MethodImplOptions.InternalCall)]
 		internal static extern void monodroid_unhandled_exception (Exception javaException);