Don't quit debugger when the program terminates, only after `quit`.

pkg/dartino_compiler/lib/src/worker/developer.dart

 // Copyright (c) 2015, the Dartino project authors. Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE.md file.
 
 library dartino_compiler.worker.developer;
 
 import 'dart:async' show
     Future,
     TimeoutException;
 
@@ skipping 700 matching lines @@
         // TODO(ahe): Need to continue to unwind stack.
         break;
       case VmCommandCode.ProcessCompileTimeError:
         state.log("Compile-time error");
         exitCode = exit_codes.DART_VM_EXITCODE_COMPILE_TIME_ERROR;
         await printTrace();
         // TODO(ahe): Continue to unwind stack?
         break;
 
       case VmCommandCode.ProcessTerminated:
+        await vmContext.terminate();
         exitCode = 0;
         break;
 
       case VmCommandCode.ConnectionError:
         state.log("Error on connection to Dartino VM: ${command.error}");
         exitCode = exit_codes.COMPILER_EXITCODE_CONNECTION_ERROR;
         break;
 
       default:
         throwInternalError("Unexpected result from Dartino VM: '$command'");
@@ skipping 1410 matching lines @@
     addIfNotNull("open_ocd_board", open_ocd_board);
     return result;
   }
 }
 
 Uri defaultSnapshotLocation(Uri script) {
   // TODO(sgjesse): Use a temp directory for the snapshot.
   String snapshotName = basenameWithoutExtension(script.path) + '.snapshot';
   return script.resolve(snapshotName);
 }