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

chrome/browser/about_flags.cc

Index: chrome/browser/about_flags.cc
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index cf5fcf4c1b40f028ed75abc33c059eaf19512bfc..145cb732a3e168cc6bd4c499b5fc011a3b0be582 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -1966,6 +1966,15 @@ const Experiment kExperiments[] = {
     SINGLE_VALUE_TYPE(app_list::switches::kEnableExperimentalAppList)
   },
 #endif
+#if defined(OS_CHROMEOS)
+  {
+    "migrate-xkb",
+    IDS_FLAGS_MIGRATE_XKB_NAME,
+    IDS_FLAGS_MIGRATE_XKB_DESCRIPTION,
+    kOsCrOS,
+    SINGLE_VALUE_TYPE(chromeos::switches::kMigrateXkb)

[Seigo Nonaka, 2014/02/28 06:14:07]

To use extension wrapped keyboard layouts by default, how about change this flag
to "use-legacy-xkb" or "disable-extension-keyboards"? Then you can enable by
default except for the flag is passed.

BTW, I don't think any visible changes are expected with this migration. So that
no flags are necessary I think.
Even if you fails the migration, you have still chance to migrate from extension
IDs to the old xkb:* values.

[Shu Chen, 2014/02/28 07:32:50]

I've removed the runtime flag, and use a hard coded flag.

+  },
+#endif
 };
 
 const Experiment* experiments = kExperiments;