[iOS] Unfocus omnibox when long pressing NTP element

This CL makes sure that when the user long presses on an element
displayed on the NTP, we unfocus the omnibox before showing the popup
menu.

Bug: 928237
Change-Id: I271e2eb5ca0965b05cbba8f35ef8f08e8f8ba578
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1541172
Auto-Submit: Gauthier Ambard <gambard@chromium.org>
Reviewed-by: Justin Cohen <justincohen@chromium.org>
Commit-Queue: Gauthier Ambard <gambard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#645288}

ios/chrome/browser/ui/content_suggestions/ntp_home_mediator.mm

@@ -287,6 +287,10 @@ const char kNTPHelpURL[] =
                                 atPoint:(CGPoint)touchLocation
                             atIndexPath:(NSIndexPath*)indexPath
                         readLaterAction:(BOOL)readLaterAction {
+  // Unfocus the omnibox as the omnibox can disappear when choosing some
+  // options. See crbug.com/928237.
+  [self.dispatcher cancelOmniboxEdit];
+
   ContentSuggestionsItem* suggestionsItem =
       base::mac::ObjCCastStrict<ContentSuggestionsItem>(item);
 
@@ -315,6 +319,11 @@ const char kNTPHelpURL[] =
   if ([item isKindOfClass:[ContentSuggestionsMostVisitedActionItem class]]) {
     return;
   }
+
+  // Unfocus the omnibox as the omnibox can disappear when choosing some
+  // options. See crbug.com/928237.
+  [self.dispatcher cancelOmniboxEdit];
+
   ContentSuggestionsMostVisitedItem* mostVisitedItem =
       base::mac::ObjCCastStrict<ContentSuggestionsMostVisitedItem>(item);
   self.alertCoordinator = [ContentSuggestionsAlertFactory
@@ -545,11 +554,6 @@ const char kNTPHelpURL[] =
                               /* in_incognito */ incognito,
                               /* in_background */ !incognito, kCurrentTab);
   params->origin_point = originPoint;
-  if (incognito) {
-    // Unfocus the omnibox if the new page should be opened in incognito to
-    // prevent staying stuck.
-    [self.dispatcher cancelOmniboxEdit];
-  }
   _urlLoadingService->Load(params);
 }