Remove unnecessary isolate argument from some visitors

runtime/vm/object.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/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 890 matching lines @@
   ASSERT(background_compilation_error_->IsLanguageError());
   ASSERT(!vm_isolate_snapshot_object_table_->IsSmi());
   ASSERT(vm_isolate_snapshot_object_table_->IsArray());
 }
 
 
 // An object visitor which will mark all visited objects. This is used to
 // premark all objects in the vm_isolate_ heap.
 class PremarkingVisitor : public ObjectVisitor {
  public:
-  explicit PremarkingVisitor(Isolate* isolate) : ObjectVisitor(isolate) {}
+  PremarkingVisitor() { }
 
   void VisitObject(RawObject* obj) {
     // Free list elements should never be marked.
     if (!obj->IsFreeListElement()) {
       ASSERT(obj->IsVMHeapObject());
       if (obj->IsMarked()) {
         // Precompiled objects are loaded pre-marked.
         ASSERT(Dart::IsRunningPrecompiledCode());
         ASSERT(obj->IsInstructions() ||
                obj->IsPcDescriptors() ||
@@ skipping 67 matching lines @@
   // pre-allocated in the vm isolate also.
   cls = isolate->object_store()->array_class();
   cls.set_name(Symbols::_List());
   cls = isolate->object_store()->one_byte_string_class();
   cls.set_name(Symbols::OneByteString());
 
   {
     ASSERT(isolate == Dart::vm_isolate());
     bool include_code_pages = !Dart::IsRunningPrecompiledCode();
     WritableVMIsolateScope scope(Thread::Current(), include_code_pages);
-    PremarkingVisitor premarker(isolate);
+    PremarkingVisitor premarker;
     ASSERT(isolate->heap()->UsedInWords(Heap::kNew) == 0);
     isolate->heap()->IterateOldObjects(&premarker);
     // Make the VM isolate read-only again after setting all objects as marked.
   }
 }
 
 
 void Object::InitVmIsolateSnapshotObjectTable(intptr_t len) {
   ASSERT(Isolate::Current() == Dart::vm_isolate());
   *vm_isolate_snapshot_object_table_ = Array::New(len, Heap::kOld);
@@ skipping 20772 matching lines @@
   return UserTag::null();
 }
 
 
 const char* UserTag::ToCString() const {
   const String& tag_label = String::Handle(label());
   return tag_label.ToCString();
 }
 
 }  // namespace dart