Remove legacy restart code

runtime/vm/isolate.h

 // Copyright (c) 2013, 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.
 
 #ifndef RUNTIME_VM_ISOLATE_H_
 #define RUNTIME_VM_ISOLATE_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/atomic.h"
@@ skipping 145 matching lines @@
     kKillMsg = 4,
     kAddExitMsg = 5,
     kDelExitMsg = 6,
     kAddErrorMsg = 7,
     kDelErrorMsg = 8,
     kErrorFatalMsg = 9,
 
     // Internal message ids.
     kInterruptMsg = 10,     // Break in the debugger.
     kInternalKillMsg = 11,  // Like kill, but does not run exit listeners, etc.
-    kVMRestartMsg = 12,     // Sent to isolates when vm is restarting.
   };
   // The different Isolate API message priorities for ping and kill messages.
   enum LibMsgPriority {
     kImmediateAction = 0,
     kBeforeNextEventAction = 1,
     kAsEventAction = 2
   };
 
   ~Isolate();
 
@@ skipping 346 matching lines @@
   bool IsPaused() const;
 
   bool should_pause_post_service_request() const {
     return should_pause_post_service_request_;
   }
   void set_should_pause_post_service_request(
       bool should_pause_post_service_request) {
     should_pause_post_service_request_ = should_pause_post_service_request;
   }
 
-  void PausePostRequest();
+  RawError* PausePostRequest();
 
   uword user_tag() const { return user_tag_; }
   static intptr_t user_tag_offset() { return OFFSET_OF(Isolate, user_tag_); }
   static intptr_t current_tag_offset() {
     return OFFSET_OF(Isolate, current_tag_);
   }
   static intptr_t default_tag_offset() {
     return OFFSET_OF(Isolate, default_tag_);
   }
 
@@ skipping 491 matching lines @@
   intptr_t* spawn_count_;
 
   Dart_IsolateFlags isolate_flags_;
   bool paused_;
   bool errors_are_fatal_;
 };
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_ISOLATE_H_