Add common data types for input method support.

ui/base/ime/composition.cc

Index: ui/base/ime/composition.cc
diff --git a/ui/base/ime/composition.cc b/ui/base/ime/composition.cc
new file mode 100644
index 0000000000000000000000000000000000000000..62e844ff6e87efaedc7fca10df142e557cfaa1a9
--- /dev/null
+++ b/ui/base/ime/composition.cc
@@ -0,0 +1,15 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ui/base/ime/composition.h"
+
+namespace ui {
+
+void Composition::Clear() {
+  text.clear();
+  underlines.clear();
+  selection = Range();
+}
+
+}  // namespace ui