Remove redundant variable descriptors from optimized code.

runtime/vm/debugger.h

 // 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.
 
 #ifndef VM_DEBUGGER_H_
 #define VM_DEBUGGER_H_
 
 #include "include/dart_debugger_api.h"
 
 #include "vm/object.h"
 #include "vm/port.h"
 
 namespace dart {
 
-class ActiveVariables;
 class CodeBreakpoint;
 class Isolate;
 class JSONArray;
 class JSONStream;
 class ObjectPointerVisitor;
 class RemoteObjectCache;
 class SourceBreakpoint;
 class StackFrame;
 
 // SourceBreakpoint represents a user-specified breakpoint location in
@@ skipping 141 matching lines @@
     return code_;
   }
 
   RawString* QualifiedFunctionName();
   RawString* SourceUrl();
   RawScript* SourceScript();
   RawLibrary* Library();
   intptr_t TokenPos();
   intptr_t LineNumber();
   intptr_t ColumnNumber();
-  void SetContext(const Context& ctx) { ctx_ = ctx.raw(); }
 
   // Returns true if this frame is for a function that is visible
   // to the user and can be debugged.
   bool IsDebuggable() const;
 
   // The context level of a frame is the context level at the
   // PC/token index of the frame. It determines the depth of the context
   // chain that belongs to the function of this activation frame.
   intptr_t ContextLevel();
 
   const char* ToCString();
 
   intptr_t NumLocalVariables();
 
   void VariableAt(intptr_t i,
                   String* name,
                   intptr_t* token_pos,
                   intptr_t* end_pos,
                   Object* value);
 
   RawArray* GetLocalVariables();
   RawObject* GetReceiver();
 
-  RawContext* GetSavedCurrentContext();
+  const Context& GetSavedCurrentContext();
 
   RawObject* Evaluate(const String& expr);
 
   void PrintToJSONObject(JSONObject* jsobj);
 
  private:
   void PrintContextMismatchError(const String& var_name,
                                  intptr_t ctx_slot,
                                  intptr_t frame_ctx_level,
                                  intptr_t var_ctx_level);
@@ skipping 351 matching lines @@
 
   friend class Isolate;
   friend class SourceBreakpoint;
   DISALLOW_COPY_AND_ASSIGN(Debugger);
 };
 
 
 }  // namespace dart
 
 #endif  // VM_DEBUGGER_H_