Settings: Fix overflow menu bug.

Currently the overflow menu will not work on second click if we never
go to the dialog. This is due to a early return cross check in the code.
If the overflow menu is exits by clicking somewhere else, it will close
without clear the actionMenuModel_. This is the same in the
history_list.

BUG=931969

Change-Id: Ia67886212ac6b09cdf0e7a0813ee98db8df34926
Reviewed-on: https://chromium-review.googlesource.com/c/1471972Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Commit-Queue: Maggie Cai <mxcai@chromium.org>
Cr-Commit-Position: refs/heads/master@{#632395}

chrome/browser/resources/settings/site_settings/all_sites.js

@@ -374,9 +374,6 @@ Polymer({
    * @private
    */
   onOpenMenu_: function(e) {
-    if (this.actionMenuModel_) {
-      return;
-    }
     const index = e.detail.index;
     const list = /** @type {IronListElement} */ (this.$['allSitesList']);
     if (index < list.firstVisibleIndex || index > list.lastVisibleIndex) {