Make hidden initializing formal parameters invisible to the debugger

runtime/vm/scopes.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_SCOPES_H_
 #define VM_SCOPES_H_
 
 #include "vm/allocation.h"
 #include "vm/assembler.h"
 #include "vm/growable_array.h"
@@ skipping 52 matching lines @@
 
   // Assign an index to a local.
   void set_index(int index) {
     ASSERT(index != kUninitializedIndex);
     index_ = index;
   }
 
   void set_invisible(bool value) {
     is_invisible_ = value;
   }
+  bool is_invisible() const { return is_invisible_; }
 
   bool IsConst() const {
     return const_value_ != NULL;
   }
 
   void SetConstValue(const Instance& value) {
     ASSERT(value.IsZoneHandle() || value.IsReadOnlyHandle());
     const_value_ = &value;
   }
 
@@ skipping 282 matching lines @@
   intptr_t end_token_pos_;    // Token index of end of scope.
   GrowableArray<LocalVariable*> variables_;
   GrowableArray<SourceLabel*> labels_;
 
   DISALLOW_COPY_AND_ASSIGN(LocalScope);
 };
 
 }  // namespace dart
 
 #endif  // VM_SCOPES_H_