Bug 1801836 - Remove no longer necessary 'from __future__' imports. r=linter-reviewers,glandium,webdriver-reviewers,perftest-reviewers,geckoview-reviewers,jld,ahal,owlish,afinder DONTBUILD

Differential Revision: https://phabricator.services.mozilla.com/D165395

build/mach_initialize.py

@@ -2,8 +2,6 @@
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
-from __future__ import division, print_function, unicode_literals
-
 import math
 import os
 import shutil