[edje_entry] Add null checking for name of anchor and item.

[edje_entry] Add null checking for name of anchor and item.

Summary:
Even if the anchor name is null, it will be appended to "anchors".
There are many null checking for name of anchor.
So it should be checked in geometry_get functions.

Test Plan:
Test with text "<a href =abc>We can't find name in this case</a>".
This text makes break the application. Because of a space between "href" and "=".
The name of anchor will be saved as null in "anchors".

Reviewers: woohyun, tasn, cedric

CC: cedric, raster
Differential Revision: https://phab.enlightenment.org/D318