Improve NoSuchMethodError error messages

runtime/vm/object.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_OBJECT_H_
 #define VM_OBJECT_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ skipping 1398 matching lines @@
       const AbstractTypeArguments& instantiator,
       NameVisibility name_visibility) const {
     const bool instantiate = true;
     return BuildSignature(instantiate, name_visibility, instantiator);
   }
 
   // Returns true if the signature of this function is instantiated, i.e. if it
   // does not involve generic parameter types or generic result type.
   bool HasInstantiatedSignature() const;
 
+  // Build a string of the form 'T, {b: B, c: C} representing the user
+  // visible formal parameters of the function.
+  RawString* UserVisibleFormalParameters() const;
+
   RawClass* Owner() const;
   RawClass* origin() const;
   RawScript* script() const;
 
   RawAbstractType* result_type() const { return raw_ptr()->result_type_; }
   void set_result_type(const AbstractType& value) const;
 
   RawAbstractType* ParameterTypeAt(intptr_t index) const;
   void SetParameterTypeAt(intptr_t index, const AbstractType& value) const;
   RawArray* parameter_types() const { return raw_ptr()->parameter_types_; }
@@ skipping 427 matching lines @@
   void set_is_external(bool value) const;
   void set_parent_function(const Function& value) const;
   void set_owner(const Object& value) const;
   RawFunction* implicit_closure_function() const;
   void set_implicit_closure_function(const Function& value) const;
   void set_num_optional_parameters(intptr_t value) const;  // Encoded value.
   void set_kind_tag(intptr_t value) const;
   void set_data(const Object& value) const;
   static RawFunction* New();
 
+  void BuildSinatureParameters(bool instantiate,
+                               NameVisibility name_visibility,
+                               const AbstractTypeArguments& instantiator,
+                               const GrowableObjectArray& pieces) const;
   RawString* BuildSignature(bool instantiate,
                             NameVisibility name_visibility,
                             const AbstractTypeArguments& instantiator) const;
 
   // Check the subtype or 'more specific' relationship.
   bool TypeTest(TypeTestKind test_kind,
                 const AbstractTypeArguments& type_arguments,
                 const Function& other,
                 const AbstractTypeArguments& other_type_arguments,
                 Error* bound_error) const;
@@ skipping 4308 matching lines @@
 
 
 RawObject* MegamorphicCache::GetTargetFunction(const Array& array,
                                                intptr_t index) {
   return array.At((index * kEntryLength) + kTargetFunctionIndex);
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_