Just remember Material Design is a set of GUIDELINES, you don't need to follow them to the A. As a matter of fact, in some specific cases many designers and developers (me included) do the EXACT OPPOSITE to what Material Design guidelines suggests. A common example is buttons statuses, there's a lot of discussion on how is Material button's approach correct, even in this same site.

All this introduction is to give you the answer to your question, which is: do whatever you want as long as the important part of the toolbar specs is respected, which is the z-index and 3d-ish aspect provided by shadows that you can see in both your examples. Note that this is for sheet steps like in your examples, because you could use different seams as well, but for your scenario, the 3d aspect is paramount, and the most widely used. 

You can see more examples and user cases at Structure --> Structure of Toolbars, and you can see the suggested amount of elevation for each element. While you'll see there's no line in any sample, you can do it if you want, just be careful that your decorative element doesn't collide with element's behavior. For example, that line looks like an active tab, and it's weird that you get that by default in Android, just tested it out of curiosity and really not getting that bottom border, are you sure you don't have some style or using a wrong element there?

Material design - how the action moded toolbar should look like
I made a custom content type to replace comments, as the current comment options are not satisfactory for me. Anonymous users can create this content type (comment).

I need to send an email to the administrator users each time a new comment is written, to allow them to publish the new comments.

I searched for notification email, but it is not what I expected; it only allows to send emails on regular basis. Maybe I could not make it work.

How can I send automatic emails to administrators to notify them a new comment has been created, and it is waiting for approval?
