Add a flag for shelf hover previews

Change-Id: If84fcb785bdc4e95e5b218e4634912ab6a3d132c
Reviewed-on: https://chromium-review.googlesource.com/1037779
Reviewed-by: Alex Newcomer <[email protected]>
Commit-Queue: Manu Cornet <[email protected]>
Cr-Commit-Position: refs/heads/master@{#555197}
diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
index 54315a8..492c9da 100644
--- a/chrome/browser/flag_descriptions.h
+++ b/chrome/browser/flag_descriptions.h
@@ -861,6 +861,9 @@
 extern const char kSettingsWindowName[];
 extern const char kSettingsWindowDescription[];
 
+extern const char kShelfHoverPreviewsName[];
+extern const char kShelfHoverPreviewsDescription[];
+
 extern const char kShowAllDialogsWithViewsToolkitName[];
 extern const char kShowAllDialogsWithViewsToolkitDescription[];