Refactor VMTagScope to Thread* rather than Isolate*.

runtime/vm/heap.cc

 // Copyright (c) 2012, 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/heap.h"
 
 #include "platform/assert.h"
 #include "platform/utils.h"
 #include "vm/flags.h"
 #include "vm/isolate.h"
@@ skipping 294 matching lines @@
     return raw_obj;
   }
   raw_obj = FindObjectInCodeSpace(visitor);
   return raw_obj;
 }
 
 
 void Heap::CollectGarbage(Space space,
                           ApiCallbacks api_callbacks,
                           GCReason reason) {
+  Thread* thread = Thread::Current();
   TIMERSCOPE(isolate(), time_gc);
   bool invoke_api_callbacks = (api_callbacks == kInvokeApiCallbacks);
   switch (space) {
     case kNew: {
-      VMTagScope tagScope(isolate(), VMTag::kGCNewSpaceTagId);
+      VMTagScope tagScope(thread, VMTag::kGCNewSpaceTagId);
       TimelineDurationScope tds(isolate(),
                                 isolate()->GetGCStream(),
                                 "CollectNewGeneration");
       RecordBeforeGC(kNew, reason);
       UpdateClassHeapStatsBeforeGC(kNew);
       new_space_.Scavenge(invoke_api_callbacks);
       isolate()->class_table()->UpdatePromoted();
       UpdatePretenurePolicy();
       RecordAfterGC();
       PrintStats();
       if (old_space_.NeedsGarbageCollection()) {
         // Old collections should call the API callbacks.
         CollectGarbage(kOld, kInvokeApiCallbacks, kPromotion);
       }
       break;
     }
     case kOld:
     case kCode: {
-      VMTagScope tagScope(isolate(), VMTag::kGCOldSpaceTagId);
+      VMTagScope tagScope(thread, VMTag::kGCOldSpaceTagId);
       TimelineDurationScope tds(isolate(),
                                 isolate()->GetGCStream(),
                                 "CollectOldGeneration");
       RecordBeforeGC(kOld, reason);
       UpdateClassHeapStatsBeforeGC(kOld);
       old_space_.MarkSweep(invoke_api_callbacks);
       RecordAfterGC();
       PrintStats();
       break;
     }
@@ skipping 17 matching lines @@
   if (space == kOld) {
     CollectGarbage(space, kInvokeApiCallbacks, kOldSpace);
   } else {
     ASSERT(space == kNew);
     CollectGarbage(space, kInvokeApiCallbacks, kNewSpace);
   }
 }
 
 
 void Heap::CollectAllGarbage() {
+  Thread* thread = Thread::Current();
   TIMERSCOPE(isolate(), time_gc);
   {
-    VMTagScope tagScope(isolate(), VMTag::kGCNewSpaceTagId);
+    VMTagScope tagScope(thread, VMTag::kGCNewSpaceTagId);
     TimelineDurationScope tds(isolate(),
                               isolate()->GetGCStream(),
                               "CollectNewGeneration");
     RecordBeforeGC(kNew, kFull);
     UpdateClassHeapStatsBeforeGC(kNew);
     new_space_.Scavenge(kInvokeApiCallbacks);
     isolate()->class_table()->UpdatePromoted();
     UpdatePretenurePolicy();
     RecordAfterGC();
     PrintStats();
   }
   {
-    VMTagScope tagScope(isolate(), VMTag::kGCOldSpaceTagId);
+    VMTagScope tagScope(thread, VMTag::kGCOldSpaceTagId);
     TimelineDurationScope tds(isolate(),
                               isolate()->GetGCStream(),
                               "CollectOldGeneration");
     RecordBeforeGC(kOld, kFull);
     UpdateClassHeapStatsBeforeGC(kOld);
     old_space_.MarkSweep(kInvokeApiCallbacks);
     RecordAfterGC();
     PrintStats();
   }
 }
@@ skipping 363 matching lines @@
     heap->DisableGrowthControl();
 }
 
 
 NoHeapGrowthControlScope::~NoHeapGrowthControlScope() {
     Heap* heap = reinterpret_cast<Isolate*>(isolate())->heap();
     heap->SetGrowthControlState(current_growth_controller_state_);
 }
 
 }  // namespace dart