Fixed compilation time measurement, restructure some code.

runtime/vm/timer.h

 // Copyright (c) 2011, 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 VM_TIMER_H_
 #define VM_TIMER_H_
 
 #include "vm/allocation.h"
 #include "vm/flags.h"
 #include "vm/os.h"
@@ skipping 20 matching lines @@
   void Stop() {
     if (enabled_) {
       ASSERT(start_ != 0);
       ASSERT(running());
       stop_ = OS::GetCurrentTimeMicros();
       total_ += ElapsedMicros();
       running_ = false;
     }
   }
 
   // Get total cummulative elapsed time in micros and reset the counters.

[hausner, 2012/05/08 21:41:01]

Please adjust the comment. I think this was originally Siva's code, so me have
an answer as to why the Reset was here. 

[srdjan, 2012/05/08 21:51:31]

Done.

-  int64_t TotalElapsedTime() {
+  int64_t TotalElapsedTime() const {
     if (enabled_) {
       int64_t result = total_;
-      Reset();
       return result;
     }
     return 0;
   }
 
   // Accessors.
   bool enabled() const { return enabled_; }
   bool running() const { return running_; }
   const char* message() const { return message_; }
 
@@ skipping 77 matching lines @@
 
 // The class TimerScope is used to start and stop a timer within a scope.
 // It is used as follows:
 // {
 //   TIMERSCOPE(name_of_timer);
 //   ....
 //   .....
 //   code that needs to be timed.
 //   ....
 // }
-class TimerScope : public ValueObject {
+class TimerScope : public StackResource {
  public:
-  TimerScope(bool flag, Timer* timer)
-      : flag_(flag), nested_(false), timer_(timer) {
+  TimerScope(bool flag, Timer* timer, BaseIsolate* isolate = NULL)
+      : StackResource(isolate), flag_(flag), nested_(false), timer_(timer) {
     if (flag_) {
       if (!timer_->running()) {
         timer_->Start();
       } else {
         nested_ = true;
       }
     }
   }
   ~TimerScope() {
     if (flag_) {
@@ skipping 10 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(TimerScope);
 };
 
 #define TIMERSCOPE(name)                                                       \
   TimerScope vm_internal_timer_((FLAG_##name || FLAG_time_all),                \
                                 &(Isolate::Current()->timer_list().name()))
 
 }  // namespace dart
 
 #endif  // VM_TIMER_H_