Simplify timeline backend

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/growable_array.h"
 #include "vm/isolate.h"
 #include "vm/lockers.h"
 #include "vm/log.h"
@@ skipping 164 matching lines @@
 #define REUSABLE_HANDLE_INITIALIZERS(object)                                   \
   object##_handle_(NULL),
 
 
 Thread::Thread(bool init_vm_constants)
     : id_(OSThread::GetCurrentThreadId()),
       thread_interrupt_callback_(NULL),
       thread_interrupt_data_(NULL),
       isolate_(NULL),
       heap_(NULL),
+      timeline_block_(NULL),
       store_buffer_block_(NULL),
       log_(new class Log()),
       deopt_id_(0),
       vm_tag_(0),
       REUSABLE_HANDLE_LIST(REUSABLE_HANDLE_INITIALIZERS)
       REUSABLE_HANDLE_LIST(REUSABLE_HANDLE_SCOPE_INIT)
       reusable_handles_(),
       cha_(NULL),
       no_callback_scope_depth_(0),
       thread_list_next_(NULL) {
@@ skipping 327 matching lines @@
 Thread* ThreadIterator::Next() {
   ASSERT(Thread::thread_list_lock_ != NULL);
   ASSERT(Thread::thread_list_lock_->IsOwnedByCurrentThread());
   Thread* current = next_;
   next_ = next_->thread_list_next_;
   return current;
 }
 
 
 }  // namespace dart