Moves the top_ and end_ words of the Scavenger into mutator thread.

runtime/vm/thread.cc

 // 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.
 
 #include "vm/thread.h"
 
 #include "vm/compiler_stats.h"
 #include "vm/dart_api_state.h"
 #include "vm/growable_array.h"
 #include "vm/isolate.h"
@@ skipping 44 matching lines @@
 #endif  // defined(DEBUG)
 
 #define REUSABLE_HANDLE_INITIALIZERS(object) object##_handle_(NULL),
 
 Thread::Thread(Isolate* isolate)
     : BaseThread(false),
       stack_limit_(0),
       stack_overflow_flags_(0),
       isolate_(NULL),
       heap_(NULL),
+      top_(0),
+      end_(0),
       top_exit_frame_info_(0),
       store_buffer_block_(NULL),
       vm_tag_(0),
       task_kind_(kUnknownTask),
       async_stack_trace_(StackTrace::null()),
       dart_stream_(NULL),
       os_thread_(NULL),
       thread_lock_(new Monitor()),
       zone_(NULL),
       current_zone_capacity_(0),
@@ skipping 782 matching lines @@
 
 DisableThreadInterruptsScope::~DisableThreadInterruptsScope() {
   if (thread() != NULL) {
     OSThread* os_thread = thread()->os_thread();
     ASSERT(os_thread != NULL);
     os_thread->EnableThreadInterrupts();
   }
 }
 
 }  // namespace dart