Remove unnecessary isolate argument from some visitors

runtime/vm/visitor.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_VISITOR_H_
 #define VM_VISITOR_H_
 
 #include "vm/allocation.h"
 #include "vm/globals.h"
 #include "vm/growable_array.h"
 
 namespace dart {
 
 // Forward declarations.
 class Isolate;
 class RawObject;
 
 // An object pointer visitor interface.
 class ObjectPointerVisitor {
  public:
-  explicit ObjectPointerVisitor(Isolate* isolate) : isolate_(isolate) {}
-  virtual ~ObjectPointerVisitor() {}
+  explicit ObjectPointerVisitor(Isolate* isolate) : isolate_(isolate) { }
+  virtual ~ObjectPointerVisitor() { }
 
   Isolate* isolate() const { return isolate_; }
 
   // Range of pointers to visit 'first' <= pointer <= 'last'.
   virtual void VisitPointers(RawObject** first, RawObject** last) = 0;
 
   virtual bool visit_function_code() const { return true; }
   virtual void add_skipped_code_function(RawFunction* funct) {
     UNREACHABLE();
   }
   // len argument is the number of pointers to visit starting from 'p'.
   void VisitPointers(RawObject** p, intptr_t len) {
     VisitPointers(p, (p + len - 1));
   }
 
   void VisitPointer(RawObject** p) { VisitPointers(p , p); }
 
  private:
   Isolate* isolate_;
   NoSafepointScope no_safepoints_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(ObjectPointerVisitor);
 };
 
 
 // An object visitor interface.
 class ObjectVisitor {
  public:
-  explicit ObjectVisitor(Isolate* isolate) : isolate_(isolate) {}
+  ObjectVisitor() { }
 
-  virtual ~ObjectVisitor() {}
-
-  Isolate* isolate() const { return isolate_; }
+  virtual ~ObjectVisitor() { }
 
   // Invoked for each object.
   virtual void VisitObject(RawObject* obj) = 0;
 
  private:
-  Isolate* isolate_;
-
   DISALLOW_COPY_AND_ASSIGN(ObjectVisitor);
 };
 
 
 // An object finder visitor interface.
 class FindObjectVisitor {
  public:
-  explicit FindObjectVisitor(Isolate* isolate) : isolate_(isolate) {}
-  virtual ~FindObjectVisitor() {}
+  FindObjectVisitor() { }
+  virtual ~FindObjectVisitor() { }
 
   // Allow to specify a address filter.
   virtual uword filter_addr() const { return 0; }
   bool VisitRange(uword begin_addr, uword end_addr) const {
     uword addr = filter_addr();
     return (addr == 0) || ((begin_addr <= addr) && (addr < end_addr));
   }
 
   // Check if object matches find condition.
   virtual bool FindObject(RawObject* obj) const = 0;
 
  private:
-  Isolate* isolate_;
-
-  DISALLOW_IMPLICIT_CONSTRUCTORS(FindObjectVisitor);
+  DISALLOW_COPY_AND_ASSIGN(FindObjectVisitor);
 };
 
 }  // namespace dart
 
 #endif  // VM_VISITOR_H_