Show tooltip with local variable value in 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 892 matching lines @@
   jsobj->AddProperty("tokenPos", TokenPos());
   jsobj->AddProperty("function", function(), !full);
   jsobj->AddProperty("code", code());
   {
     JSONArray jsvars(jsobj, "vars");
     const int num_vars = NumLocalVariables();
     for (intptr_t v = 0; v < num_vars; v++) {
       JSONObject jsvar(&jsvars);
       String& var_name = String::Handle();
       Instance& var_value = Instance::Handle();
-      intptr_t unused;
-      VariableAt(v, &var_name, &unused, &unused, &var_value);
+      intptr_t token_pos;
+      intptr_t end_token_pos;
+      VariableAt(v, &var_name, &token_pos, &end_token_pos, &var_value);
       jsvar.AddProperty("name", var_name.ToCString());
       jsvar.AddProperty("value", var_value, !full);
+      jsvar.AddProperty("tokenPos", token_pos);
+      jsvar.AddProperty("endTokenPos", end_token_pos);
     }
   }
 }
 
 
 
 void DebuggerStackTrace::AddActivation(ActivationFrame* frame) {
   if (FLAG_show_invisible_frames || frame->function().is_visible()) {
     trace_.Add(frame);
   }
@@ skipping 1765 matching lines @@
 }
 
 
 void Debugger::RegisterCodeBreakpoint(CodeBreakpoint* bpt) {
   ASSERT(bpt->next() == NULL);
   bpt->set_next(code_breakpoints_);
   code_breakpoints_ = bpt;
 }
 
 }  // namespace dart