[XABT] Use a response file for D8 task.

Author: jpobst

src/Xamarin.Android.Build.Tasks/Tasks/D8.cs

@@ -4,6 +4,7 @@
 using System.IO;
 using Xamarin.Android.Tools;
 using Microsoft.Android.Build.Tasks;
+using System.Text;
 
 namespace Xamarin.Android.Tasks
 {
@@ -43,10 +44,27 @@ public class D8 : JavaToolTask
 		public string ExtraArguments { get; set; }
 
 		protected override string GenerateCommandLineCommands ()
+		{
+			var cmd = new CommandLineBuilder ();
+
+			if (!string.IsNullOrEmpty (JavaOptions)) {
+				cmd.AppendSwitch (JavaOptions);
+			}
+
+			cmd.AppendSwitchIfNotNull ("-Xmx", JavaMaximumHeapSize);
+			cmd.AppendSwitchIfNotNull ("-classpath ", JarPath);
+			cmd.AppendSwitch (MainClass);
+
+			return cmd.ToString ();
+		}
+
+		protected override string GenerateResponseFileCommands ()
 		{
 			return GetCommandLineBuilder ().ToString ();
 		}
 
+		protected override Encoding ResponseFileEncoding => Encoding.UTF8;
+
 		protected virtual string MainClass => "com.android.tools.r8.D8";
 
 		protected int MinSdkVersion { get; set; }
@@ -55,13 +73,6 @@ protected virtual CommandLineBuilder GetCommandLineBuilder ()
 		{
 			var cmd = new CommandLineBuilder ();
 
-			if (!string.IsNullOrEmpty (JavaOptions)) {
-				cmd.AppendSwitch (JavaOptions);
-			}
-			cmd.AppendSwitchIfNotNull ("-Xmx", JavaMaximumHeapSize);
-			cmd.AppendSwitchIfNotNull ("-classpath ", JarPath);
-			cmd.AppendSwitch (MainClass);
-
 			if (!string.IsNullOrEmpty (ExtraArguments))
 				cmd.AppendSwitch (ExtraArguments); // it should contain "--dex".
 			if (Debug)