Fix focus issues with web contents modal dialogs.

BUG=880210
TEST=as in bug

Change-Id: I9f305084bf9f6b146d0323baeabc4437466857df
Reviewed-on: https://chromium-review.googlesource.com/1252241Reviewed-by: Leonard Grey <lgrey@chromium.org>
Commit-Queue: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#595171}

chrome/browser/ui/views/tab_contents/chrome_web_contents_view_focus_helper.cc

@@ -38,8 +38,10 @@ bool ChromeWebContentsViewFocusHelper::Focus() {
 
   const web_modal::WebContentsModalDialogManager* manager =
       web_modal::WebContentsModalDialogManager::FromWebContents(web_contents_);
-  if (manager && manager->IsDialogActive())
+  if (manager && manager->IsDialogActive()) {
     manager->FocusTopmostDialog();
+    return true;
+  }
 
   return false;
 }