Add IME service flag on ChromeOS.

This flag will provide entry for users to enable the IME service.

Bug: 888885
Change-Id: Ie21e5d1afd001db6968ce69d248304fad35bc31e
Reviewed-on: https://chromium-review.googlesource.com/c/1319223
Reviewed-by: Scott Violet <[email protected]>
Commit-Queue: Leo Zhang <[email protected]>
Cr-Commit-Position: refs/heads/master@{#605893}
diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
index 320c683f..9076fd0 100644
--- a/chrome/browser/flag_descriptions.h
+++ b/chrome/browser/flag_descriptions.h
@@ -2060,6 +2060,9 @@
 extern const char kInputViewName[];
 extern const char kInputViewDescription[];
 
+extern const char kImeServiceName[];
+extern const char kImeServiceDescription[];
+
 extern const char kLockScreenNotificationName[];
 extern const char kLockScreenNotificationDescription[];