Fixing indexing and text offset problems in injectCFIMarkerIntoText.

[marcuswu]

This change fixes a couple of situations where injectCFIMarkerIntoText would index into the text node list or calculate offsets into text incorrectly. It also makes the method more CFI spec compliant by allowing for injection after the last character of a text node.

[bormind]

Hi Marcus, thank you for looking into this.

Currently cfi code in readium-shared-js/libemub_cfi.js is not automatically synchronized with epubcfi project (https://github.com/readium/EPUBCFI) but this is where emub_cfi.js comes from. We just replace the one in readium-shared-js/lib with one from EPUBCFI project.
Could you please make sure that you changes are in EPUBCFI project. Than we will just do the replace of the emub_cfi.js in readium-shared-js/lib/emub_cfi.js. Otherwise we may loose your changes.

Boris.

[marcuswu]

Ok, thanks. I've submitted a pull request to the EPUBCFI project.

[marcuswu]

The pull request to the EPUBCFI project has been accepted. Should I just close this one?

[bormind]

Marcus, updated epub_cfi now in the readium-shared-js. You can close the request.

Thanks.

[marcuswu]

Thanks