Update handling of ambiguous name references

runtime/vm/mirrors_api_impl.cc

 // Copyright (c) 2013, 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 "include/dart_mirrors_api.h"
 
 #include "platform/assert.h"
 #include "vm/class_finalizer.h"
 #include "vm/dart.h"
 #include "vm/dart_api_impl.h"
@@ skipping 145 matching lines @@
     // Case 4.  Lookup the function with a . appended to find the
     // unnamed constructor.
     if (func.IsNull()) {
       tmp_name = String::Concat(func_name, Symbols::Dot());
       func = cls.LookupFunctionAllowPrivate(tmp_name);
     }
   } else if (obj.IsLibrary()) {
     const Library& lib = Library::Cast(obj);
 
     // Case 1.  Lookup the unmodified function name.
-    String& ambiguity_error_msg = String::Handle(isolate);
-    func = lib.LookupFunctionAllowPrivate(func_name, &ambiguity_error_msg);
+    func = lib.LookupFunctionAllowPrivate(func_name);
 
     // Case 2.  Lookup the function without the external setter suffix
     // '='.  Make sure to do this check after the regular lookup, so
     // that we don't interfere with operator lookups (like ==).
-    if (func.IsNull() && ambiguity_error_msg.IsNull() &&
-        HasExternalSetterSuffix(func_name)) {
+    if (func.IsNull() && HasExternalSetterSuffix(func_name)) {
       tmp_name = RemoveExternalSetterSuffix(func_name);
       tmp_name = Field::SetterName(tmp_name);
-      func = lib.LookupFunctionAllowPrivate(tmp_name, &ambiguity_error_msg);
+      func = lib.LookupFunctionAllowPrivate(tmp_name);
     }
 
     // Case 3.  Lookup the function with the getter prefix prepended.
-    if (func.IsNull() && ambiguity_error_msg.IsNull()) {
+    if (func.IsNull()) {
       tmp_name = Field::GetterName(func_name);
-      func = lib.LookupFunctionAllowPrivate(tmp_name, &ambiguity_error_msg);
-    }
-    if (!ambiguity_error_msg.IsNull()) {
-      return Api::NewError("%s.", ambiguity_error_msg.ToCString());
+      func = lib.LookupFunctionAllowPrivate(tmp_name);
     }
   } else {
     return Api::NewError(
         "%s expects argument 'target' to be a class or library.",
         CURRENT_FUNC);
   }
 
 #if defined(DEBUG)
   if (!func.IsNull()) {
     // We only provide access to a subset of function kinds.
@@ skipping 169 matching lines @@
     RETURN_TYPE_ERROR(isolate, closure, Instance);
   }
 
   ASSERT(ClassFinalizer::AllClassesFinalized());
 
   RawFunction* rf = Closure::function(closure_obj);
   return Api::NewHandle(isolate, rf);
 }
 
 }  // namespace dart