Remove signature classes from the VM.

runtime/lib/errors.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/bootstrap_natives.h"
 #include "vm/exceptions.h"
 #include "vm/object_store.h"
 #include "vm/runtime_entry.h"
 #include "vm/stack_frame.h"
 
@@ skipping 49 matching lines @@
 DEFINE_NATIVE_ENTRY(TypeError_throwNew, 5) {
   // No need to type check the arguments. This function can only be called
   // internally from the VM.
   intptr_t location = Smi::CheckedHandle(arguments->NativeArgAt(0)).Value();
   const Instance& src_value =
       Instance::CheckedHandle(arguments->NativeArgAt(1));
   const String& dst_type_name =
       String::CheckedHandle(arguments->NativeArgAt(2));
   const String& dst_name = String::CheckedHandle(arguments->NativeArgAt(3));
   const String& error_msg = String::CheckedHandle(arguments->NativeArgAt(4));
-  const String& src_type_name =
-      String::Handle(Type::Handle(src_value.GetType()).UserVisibleName());
+  const String& src_type_name = String::Handle(
+      AbstractType::Handle(src_value.GetType()).UserVisibleName());
   Exceptions::CreateAndThrowTypeError(location, src_type_name,
                                       dst_type_name, dst_name, error_msg);
   UNREACHABLE();
   return Object::null();
 }
 
 
 // Allocate and throw a new FallThroughError.
 // Arg0: index of the case clause token into which we fall through.
 // Return value: none, throws an exception.
@@ skipping 46 matching lines @@
 
 // Rethrow an error with a stacktrace.
 DEFINE_NATIVE_ENTRY(Async_rethrow, 2) {
   GET_NON_NULL_NATIVE_ARGUMENT(Instance, error, arguments->NativeArgAt(0));
   GET_NON_NULL_NATIVE_ARGUMENT(Instance, stacktrace, arguments->NativeArgAt(1));
   Exceptions::ReThrow(thread, error, stacktrace);
   return Object::null();
 }
 
 }  // namespace dart