Implement 'print', 'up', 'down', and 'frame' commands in the Observatory debugger.

runtime/observatory/lib/src/service/object.dart

Index: runtime/observatory/lib/src/service/object.dart
diff --git a/runtime/observatory/lib/src/service/object.dart b/runtime/observatory/lib/src/service/object.dart
index 71c6a09682c5139f00514899c99a8d431b6a6e8e..2bd63a29510ec63f6207369a28d55400e882710d 100644
--- a/runtime/observatory/lib/src/service/object.dart
+++ b/runtime/observatory/lib/src/service/object.dart
@@ -1135,16 +1135,12 @@ class Isolate extends ServiceObjectOwner with Coverage {
                      { 'breakpointId': bpt.id });
   }
 
-  // TODO(turnidge): If the user invokes pause (or other rpcs) twice,
-  // they could get a race.  Consider returning an "in progress"
-  // future to avoid this.
   Future pause() {
     return invokeRpc('pause', {}).then((result) {
         if (result is DartError) {
           // TODO(turnidge): Handle this more gracefully.
           Logger.root.severe(result.message);
         }
-        return isolate.reload();
       });
   }
 
@@ -1154,7 +1150,6 @@ class Isolate extends ServiceObjectOwner with Coverage {
           // TODO(turnidge): Handle this more gracefully.
           Logger.root.severe(result.message);
         }
-        return isolate.reload();
       });
   }
 
@@ -1164,7 +1159,6 @@ class Isolate extends ServiceObjectOwner with Coverage {
           // TODO(turnidge): Handle this more gracefully.
           Logger.root.severe(result.message);
         }
-        return isolate.reload();
       });
   }
 
@@ -1174,7 +1168,6 @@ class Isolate extends ServiceObjectOwner with Coverage {
           // TODO(turnidge): Handle this more gracefully.
           Logger.root.severe(result.message);
         }
-        return isolate.reload();
       });
   }
 
@@ -1184,7 +1177,6 @@ class Isolate extends ServiceObjectOwner with Coverage {
           // TODO(turnidge): Handle this more gracefully.
           Logger.root.severe(result.message);
         }
-        return isolate.reload();
       });
   }
 
@@ -1207,6 +1199,15 @@ class Isolate extends ServiceObjectOwner with Coverage {
     return invokeRpc('eval', params);
   }
 
+  Future<ServiceObject> evalFrame(int framePos,
+                                  String expression) {
+    Map params = {
+      'frame': framePos,
+      'expression': expression,
+    };
+    return invokeRpc('evalFrame', params);
+  }
+
   Future<ServiceObject> getRetainedSize(ServiceObject target) {
     Map params = {
       'targetId': target.id,
@@ -1935,6 +1936,7 @@ class ServiceFunction extends ServiceObject with Coverage {
       return;
     }
 
+    _loaded = true;
     isStatic = map['static'];
     isConst = map['const'];
     parent = map['parent'];