Fix assistant optin dependency

Bug: None
Test: Manual Test
Change-Id: I0e1ef57b9c148d0c5db182ff1c44564893be5973
Reviewed-on: https://chromium-review.googlesource.com/1161292Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Yue Li <updowndota@chromium.org>
Cr-Commit-Position: refs/heads/master@{#580371}

chrome/browser/resources/chromeos/assistant_optin/assistant_optin.js

@@ -5,6 +5,7 @@
 // <include src="../login/oobe_types.js">
 // <include src="../login/oobe_buttons.js">
 // <include src="../login/oobe_change_picture.js">
+// <include src="../login/oobe_dialog_host_behavior.js">
 // <include src="../login/oobe_dialog.js">
 // <include src="utils.js">
 // <include src="setting_zippy.js">