Tag is not indexed if not recognized by on-the-fly reformatting
Zim trunk, r404.
Steps to reproduce:
1) On the new line type "foo bar @baz" (no another space/Enter)
2) Tag is not recognized by on-the-fly reformatting (it's proper behavior)
3) Save page (or wait for autosave feature)
4) Tag is not indexed (not shown in tag cloud).
5) Reload the page
6) Tag was recognized by parser (brown color), but it isn't still indexed.
7) Modify the page and save.
8) The tag is finally indexed.
Tag should be indexed already in the step 4 (or in the step 6 at the latest).
The indexing code seems to use TextBuffer.