Move some common ime code to ui/base/

ui/base/gtk/gtk_im_context_util.h

+// 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.
+
+#ifndef UI_BASE_GTK_GTK_IM_CONTEXT_UTIL_H_
+#define UI_BASE_GTK_GTK_IM_CONTEXT_UTIL_H_
+#pragma once
+
+#include <pango/pango-attributes.h>
+
+namespace ui {
+
+struct CompositionText;
+
+// Extracts composition text information (text, underlines, selection range)
+// from given Gtk preedit data (utf-8 text, pango attributes, cursor position).
+void ExtractCompositionTextFromGtkPreedit(const gchar* utf8_text,
+                                          PangoAttrList* attrs,
+                                          int cursor_position,
+                                          CompositionText* composition);
+
+}  // namespace ui
+
+#endif  // UI_BASE_GTK_GTK_IM_CONTEXT_UTIL_H_