Implement case mapping using the Unicode default case mapping algorithm.

runtime/lib/string.cc

 // Copyright (c) 2011, 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/native_entry.h"
 #include "vm/object.h"
 
@@ skipping 122 matching lines @@
     GrowableArray<const Object*> args;
     Exceptions::ThrowByType(Exceptions::kIllegalArgument, args);
   }
   String& b = String::Handle();
   b  ^= b_instance.raw();
   const String& result = String::Handle(String::Concat(a, b));
   arguments->SetReturn(result);
 }
 
 
+DEFINE_NATIVE_ENTRY(String_toLowerCase, 1) {
+  const String& str = String::CheckedHandle(arguments->At(0));
+  ASSERT(!str.IsNull());
+  const String& result = String::Handle(String::ToLowerCase(str));
+  arguments->SetReturn(result);
+}
+
+
+DEFINE_NATIVE_ENTRY(String_toUpperCase, 1) {
+  const String& str = String::CheckedHandle(arguments->At(0));
+  ASSERT(!str.IsNull());
+  const String& result = String::Handle(String::ToUpperCase(str));
+  arguments->SetReturn(result);
+}
+
+
 DEFINE_NATIVE_ENTRY(Strings_concatAll, 1) {
   const Array& strings = Array::CheckedHandle(arguments->At(0));
   ASSERT(!strings.IsNull());
   const String& result = String::Handle(String::ConcatAll(strings));
   arguments->SetReturn(result);
 }
 
 }  // namespace dart