[IME] migrate the xkb ID to extension based xkb ID.

chromeos/ime/extension_ime_util.h

 // Copyright 2013 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 CHROMEOS_IME_EXTENSION_IME_UTIL_H_
 #define CHROMEOS_IME_EXTENSION_IME_UTIL_H_
 
 #include <string>
 
 #include "chromeos/chromeos_export.h"
@@ skipping 14 matching lines @@
 // nor |engine_id| is really a member of |extension_id|.
 std::string CHROMEOS_EXPORT GetComponentInputMethodID(
     const std::string& extension_id,
     const std::string& engine_id);
 
 // Returns extension ID if |input_method_id| is extension IME ID or component
 // extension IME ID. Otherwise returns an empty string ("").
 std::string CHROMEOS_EXPORT GetExtensionIDFromInputMethodID(
     const std::string& input_method_id);
 
+// Returns InputMethodID from keyboard layout (xkb) id (e.g. xkb:fr:fra).
+const std::string CHROMEOS_EXPORT GetInputMethodIDByKeyboardLayout(

[Yuki, 2014/03/04 04:04:45]

const in |const std::string| is meaningless.  If you have to return an object
(not a reference), then const doesn't make much sense.

[Shu Chen, 2014/03/04 04:45:02]

Done.

+    const std::string& keyboard_layout_id);
+
 // Returns true if |input_method_id| is extension IME ID. This function does not
 // check |input_method_id| is installed extension IME.
 bool CHROMEOS_EXPORT IsExtensionIME(const std::string& input_method_id);
 
 // Returns true if |input_method_id| is component extension IME ID. This
 // function does not check |input_method_id| is really whitelisted one or not.
 // If you want to check |input_method_id| is whitelisted component extension
 // IME, please use ComponentExtensionIMEManager::IsWhitelisted instead.
 bool CHROMEOS_EXPORT IsComponentExtensionIME(
     const std::string& input_method_id);
 
 // Returns true if the |input_method| is a member of |extension_id| of extension
 // IME, otherwise returns false.
 bool CHROMEOS_EXPORT IsMemberOfExtension(const std::string& input_method_id,
                                          const std::string& extension_id);
 
 // Returns true if the |input_method_id| is the extension based xkb keyboard,
 // otherwise returns false.
 bool CHROMEOS_EXPORT IsKeyboardLayoutExtension(
     const std::string& input_method_id);
 
+// Returns true to use the wrapped extension keyboards instead of the legacy
+// xkb keyboards, returns false otherwise.
+bool CHROMEOS_EXPORT UseWrappedExtensionKeyboardLayouts();
+
+// Sets true to forcibly let UseWrappedExtensionKeyboardLayouts() function
+// return true for testing purpose, sets false to restore.
+// Returns the original flag value.
+bool CHROMEOS_EXPORT SetUseWrappedExtensionKeyboardLayoutsFlagForTesting(

[Yuki, 2014/03/04 04:04:45]

Please consider to make this a class named ScopedFoo.
See
https://code.google.com/p/chromium/codesearch#search/&q=%5CbScoped%5B%5E%5Cs%...
for example.

base::AutoReset in base/auto_reset.h may be useful.

I'm okay to define a new class here.  I don't think it's worth making a new file
just to define the helper ScopedXxx class.

[Shu Chen, 2014/03/04 04:45:02]

Done.

+    bool enabled);
+
+// Gets legacy xkb id (e.g. xkb:us::eng) from the new extension based xkb id
+// (e.g. _comp_ime_...xkb:us::eng). If the given id is not prefixed with
+// 'xkb:', just return the same as the given id.
+const std::string CHROMEOS_EXPORT MaybeGetLegacyXkbId(

[Yuki, 2014/03/04 04:04:45]

Ditto for const in |const std::string|.

[Shu Chen, 2014/03/04 04:45:02]

Done.

+    const std::string& input_method_id);
+
 }  // namespace extension_ime_util
 
 }  // namespace chromeos
 
 #endif  // CHROMEOS_IME_EXTENSION_IME_UTIL_H_