Add a working command line debugger to Observatory.

runtime/observatory/test/debugging_test.dart

 // Copyright (c) 2015, the Dart 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 file.
 
 import 'package:observatory/service_io.dart';
 import 'package:unittest/unittest.dart';
 import 'test_helper.dart';
 import 'dart:async';
 
 void testFunction() {
@@ skipping 28 matching lines @@
 
 // Add breakpoint
 (Isolate isolate) {
   return isolate.rootLib.load().then((_) {
       // Set up a listener to wait for breakpoint events.
       Completer completer = new Completer();
       List events = [];
       isolate.vm.events.stream.listen((ServiceEvent event) {
         if (event.eventType.startsWith('Breakpoint')) {
           events.add(event);
-        }
-        if (events.length == 2) {
-          expect(events[0].eventType, equals('BreakpointResolved'));
-          expect(events[1].eventType, equals('BreakpointReached'));
-          print('Breakpoint reached');
-          completer.complete();
+          if (events.length == 2) {
+            expect(events[0].eventType, equals('BreakpointResolved'));
+            expect(events[1].eventType, equals('BreakpointReached'));
+            print('Breakpoint reached');
+            completer.complete();
+          }
         }
       });
 
       // Add the breakpoint.
       var script = isolate.rootLib.scripts[0];
       return isolate.addBreakpoint(script, 14).then((ServiceObject bpt) {
           expect(bpt is ServiceMap, isTrue);
           ServiceMap m = bpt;
           expect(m.type, equals('Breakpoint'));
           expect(m['location']['script'].id, equals(script.id));
           expect(m['location']['tokenPos'], equals(51));
-          expect(isolate.breakpoints.type, equals('BreakpointList'));
-          expect(isolate.breakpoints['breakpoints'].length, equals(1));
+          expect(isolate.breakpoints.length, equals(1));
           return completer.future;  // Wait for breakpoint events.
       });
     });
 },
 
 // Get the stack trace
 (Isolate isolate) {
   return isolate.getStack().then((ServiceMap stack) {
       expect(stack.type, equals('Stack'));
       expect(stack['frames'].length, greaterThanOrEqualTo(1));
       expect(stack['frames'][0]['function'].name, equals('testFunction'));
   });
 },
 
 // Stepping
 (Isolate isolate) {
   // Set up a listener to wait for breakpoint events.
   Completer completer = new Completer();
   List events = [];
   isolate.vm.events.stream.listen((ServiceEvent event) {
     if (event.eventType.startsWith('Breakpoint')) {
       expect(event.eventType, equals('BreakpointReached'));
+      print('Breakpoint reached');
+      completer.complete();
     }
-    print('Breakpoint reached');
-    completer.complete();
   });
   
   return isolate.stepInto().then((isolate) {
     return completer.future;  // Wait for breakpoint events.
   });
 },
 
 // Get the stack trace again.  We are in 'print'.
 (Isolate isolate) {
   return isolate.getStack().then((ServiceMap stack) {
       expect(stack.type, equals('Stack'));
       expect(stack['frames'].length, greaterThanOrEqualTo(2));
       expect(stack['frames'][0]['function'].name, equals('print'));
   });
 },
 
 // Remove breakpoint
 (Isolate isolate) {
-  expect(isolate.breakpoints['breakpoints'].length, equals(1));
-  var bpt = isolate.breakpoints['breakpoints'][0];
+  expect(isolate.breakpoints.length, equals(1));
+  var bpt = isolate.breakpoints[0];
   return isolate.removeBreakpoint(bpt).then((_) {
-      expect(isolate.breakpoints['breakpoints'].length, equals(0));
+      expect(isolate.breakpoints.length, equals(0));
   });
 },
 
 ];
 
 main(args) => runIsolateTests(args, tests, testeeConcurrent: testFunction);