Fix reported path when file name also occurs in parent directory name(s)

[ogvolkov]

Brief description of the changes

Fixes reported path (qqpath) in case when the file name in question appears in one of its parent directory names, see #1976. The original code used indexOf so if the first occurrence was not a file name itself, it stripped way too much from the path.

What browsers and operating systems have you tested these changes on?

Chrome 64.0.3282.167, FF 58.0.2, Edge 41.16299.248.0

Have you written unit tests? If not, explain why.

Unit tests are present, both for normal case where I used the value the current code returns as a reference, and for the case when directory name is the same as the file name.

[rnicholus]

just to be clear, the only change was fullPath.indexOf(name) -> fullPath.lastIndexOf(name)?

[ogvolkov]

Yes, the functional change is only that.
However to have it tested I've extracted it as a separate function, which is also a bit cleaner imo.

[rnicholus]

thanks for your work on this! I'm going to release this as 5.15.7 shortly

[rnicholus]

travis-ci is currently broken (this actually happens a lot in my experience) so i'll be able to release once that's fixed