Use a map to store uniform locations instead of a vector. Some intel drivers use seemingly arbitrary integers as uniform locations. This causes the location vector to be resized to arbitrarily large sizes. BUG=angleproject:882 Change-Id: I8db89178907dd6206eb8e646a0b426aa9bac0832 Reviewed-on: https://chromium-review.googlesource.com/274816 Reviewed-by: Kenneth Russell <kbr@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org> Tested-by: Geoff Lang <geofflang@chromium.org>