Bug 1474285 will require a simple way to separate one install from another. The full file path could be used however this is unwieldy and can contain special characters that may not be usable in the ini file we'll ultimately write to. Luckily we already have a mechanism in tree for hashing the install path. It's only on Windows right now ans not exposed in a great way but it is simple to correct that.

Profile-per-install uses a hash of the install directory to identify different installs of Firefox. This exposes the existing cityhash generated hash from nsXREDirProvider and makes it available on all platforms.

Comment on attachment 9002660 [details] Bug 1484846: Expose a unique hash for the application install directory. r=froydnj Nathan Froyd [:froydnj] has approved the revision.

Pushed by dtownsend@mozilla.com: https://hg.mozilla.org/integration/autoland/rev/8ffadc97369c Expose a unique hash for the application install directory. r=froydnj