[IME] Loads chromeos-xkb extension and add the extension based xkb keyboards in the chrome://settin…

chromeos/ime/extension_ime_util.cc

Index: chromeos/ime/extension_ime_util.cc
diff --git a/chromeos/ime/extension_ime_util.cc b/chromeos/ime/extension_ime_util.cc
index 777b18c6852de892c9775fe9665b7cc241c5d1e7..7955e52536caae6569ca3c4a917fb6f66e25ab55 100644
--- a/chromeos/ime/extension_ime_util.cc
+++ b/chromeos/ime/extension_ime_util.cc
@@ -12,6 +12,8 @@ const char kExtensionIMEPrefix[] = "_ext_ime_";
 const int kExtensionIMEPrefixLength =
     sizeof(kExtensionIMEPrefix) / sizeof(kExtensionIMEPrefix[0]) - 1;
 const char kComponentExtensionIMEPrefix[] = "_comp_ime_";
+const char kExtensionXkbIdPrefix[] =
+    "_comp_ime_fgoepimhcoialccpbmpnnblemnepkkao";
 const int kComponentExtensionIMEPrefixLength =
     sizeof(kComponentExtensionIMEPrefix) /
         sizeof(kComponentExtensionIMEPrefix[0]) - 1;
@@ -69,5 +71,9 @@ bool IsMemberOfExtension(const std::string& input_method_id,
                          true);  // Case sensitive.
 }
 
+bool IsKeyboardLayoutExtension(const std::string& input_method_id) {
+  return StartsWithASCII(input_method_id, kExtensionXkbIdPrefix, true);
+}
+
 }  // namespace extension_ime_util
 }  // namespace chromeos