Add Heap::isolate_ to simplify code.

runtime/vm/scavenger.cc

 // 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.
 
 #include "vm/scavenger.h"
 
 #include <algorithm>
 #include <map>
 #include <utility>
 
@@ skipping 237 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(ScavengerVisitor);
 };
 
 
 class ScavengerWeakVisitor : public HandleVisitor {
  public:
   // 'prologue_weak_were_strong' is currently only used for sanity checking.
   explicit ScavengerWeakVisitor(Scavenger* scavenger,
                                 bool prologue_weak_were_strong)
-      :  HandleVisitor(Isolate::Current()),
+      :  HandleVisitor(scavenger->heap_->isolate()),
          scavenger_(scavenger),
          prologue_weak_were_strong_(prologue_weak_were_strong) {
   }
 
   void VisitHandle(uword addr) {
     FinalizablePersistentHandle* handle =
       reinterpret_cast<FinalizablePersistentHandle*>(addr);
     RawObject** p = handle->raw_addr();
     if (scavenger_->IsUnreachable(p)) {
       ASSERT(!handle->IsPrologueWeakPersistent() ||
@@ skipping 421 matching lines @@
   // TODO(cshapiro): Add a decision procedure for determining when the
   // the API callbacks should be invoked.
   Scavenge(false);
 }
 
 
 void Scavenger::Scavenge(bool invoke_api_callbacks) {
   // Scavenging is not reentrant. Make sure that is the case.
   ASSERT(!scavenging_);
   scavenging_ = true;
-  Isolate* isolate = Isolate::Current();
+  Isolate* isolate = heap_->isolate();
   NoHandleScope no_handles(isolate);
 
   if (FLAG_verify_before_gc) {
     OS::PrintErr("Verifying before Scavenge...");
     heap_->Verify();
     OS::PrintErr(" done.\n");
   }
 
   // Setup the visitor and run a scavenge.
   ScavengerVisitor visitor(isolate, this);
@@ skipping 55 matching lines @@
 }
 
 
 void Scavenger::FreeExternal(intptr_t size) {
   ASSERT(size >= 0);
   external_size_ -= size;
   ASSERT(external_size_ >= 0);
 }
 
 }  // namespace dart