A duplicate set of kFaviconsPerCategoryImage constants cause compilation problems in Android jumbo builds where the constants end up in the same translation unit.

A fix landed a bit late on master through https://chromium-review.googlesource.com/c/chromium/src/+/1275895 so the M71 branch was cut in the meantime and has the same problem. This is to track backporting to M71.

Requesting approval to backport to M71 so that embedders and others building Android builds with use_jumbo_build=true for much faster compilations won't get any compilation errors.