Fix some errors in service.md.

runtime/vm/service/service.md

 # Dart VM Service Protocol 2.0
 
 > Please post feedback to the [observatory-discuss group][discuss-list]
 
 This document describes of _version 2.0_ of the Dart VM Service Protocol. This
 protocol is used to communicate with a running Dart Virtual Machine.
 
 To use the Service Protocol, start the VM with the *--observe* flag.
 The VM will start a webserver which services protocol requests via WebSocket.
 It is possible to make HTTP (non-WebSocket) requests,
@@ skipping 738 matching lines @@
 
 If the variable is being initialized, the _value_ will be the
 _BeingInitialized_ [Sentinel](#sentinel).
 
 If the variable has been optimized out by the compiler, the _value_
 will be the _OptimizedOut_ [Sentinel](#sentinel).
 
 ### Breakpoint
 
 ```
-class Breakpoint extends Response {
+class Breakpoint extends Object {
   int breakpointNumber;
   bool resolved;
   SourceLocation location;
 }
 ```
 
 A _Breakpoint_ describes a debugger breakpoint.
 
 ### Class
 
 ```
 class @Class extends @Object {
   // The name of this class.
   string name;
 }
 ```
 
 _@Class_ is a reference to a _Class_.
 
 ```
 class Class extends Object {
   // The name of this class.
   string name;
 
   // The error which occurred during class finalization, if it exists.
-  @Instance error [optional];
+  @Error error [optional];
 
   // Is this an abstract class?
   bool abstract;
 
   // Is this a const class?
   bool const;
 
   // Has this class been finalized?
   bool finalized;
 
@@ skipping 361 matching lines @@
   string valueAsString [optional];
 }
 ```
 
 A _Flag_ represents a single VM command line flag.
 
 ### FlagList
 
 ```
 class FlagList extends Response {
-  // A list of all flags which are set to default values.
-  Flag[] unmodifiedFlags;
-
-  // A list of all flags which have been modified by the user.
-  Flag[] modifiedFlags;
+  // A list of all flags in the VM.
+  Flag[] flags;
 }
 ```
 
 A _FlagList_ represents the complete set of VM command line flags.
 
 ### Frame
 
 ```
 class Frame extends Response {
   int index;
   @Function function;
   @Code code;
-  @Script script;
-  int tokenPos;
+  SourceLocation location;
   BoundVariable[] vars;
 }
 ```
 
 ### Function
 
 ```
 class @Function extends @Object {
   // The name of this function.
   string name;
@@ skipping 807 matching lines @@
 ```
 
 ## Revision History
 
 version | comments
 ------- | --------
 1.0 draft 1 | initial revision
 
 
 [discuss-list]: https://groups.google.com/a/dartlang.org/forum/#!forum/observatory-discuss