Implement 'print', 'up', 'down', and 'frame' commands in the Observatory debugger.

runtime/vm/debugger.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/debugger.h"
 
 #include "include/dart_api.h"
 
 #include "vm/code_generator.h"
 #include "vm/code_patcher.h"
@@ skipping 710 matching lines @@
 
 void ActivationFrame::VariableAt(intptr_t i,
                                  String* name,
                                  intptr_t* token_pos,
                                  intptr_t* end_pos,
                                  Object* value) {
   GetDescIndices();
   ASSERT(i < desc_indices_.length());
   intptr_t desc_index = desc_indices_[i];
   ASSERT(name != NULL);
-  *name ^= var_descriptors_.GetName(desc_index);
+
+  const String& tmp = String::Handle(var_descriptors_.GetName(desc_index));
+  *name ^= String::IdentifierPrettyName(tmp);
+
   RawLocalVarDescriptors::VarInfo var_info;
   var_descriptors_.GetInfo(desc_index, &var_info);
   ASSERT(token_pos != NULL);
   *token_pos = var_info.begin_pos;
   ASSERT(end_pos != NULL);
   *end_pos = var_info.end_pos;
   ASSERT(value != NULL);
   const int8_t kind = var_info.kind();
   if (kind == RawLocalVarDescriptors::kStackVar) {
     *value = GetLocalInstanceVar(var_info.index());
@@ skipping 1893 matching lines @@
 }
 
 
 void Debugger::RegisterCodeBreakpoint(CodeBreakpoint* bpt) {
   ASSERT(bpt->next() == NULL);
   bpt->set_next(code_breakpoints_);
   code_breakpoints_ = bpt;
 }
 
 }  // namespace dart