Bug 1742628 - Part 1: Enable non-unified builds for js/src/util. r=tc…

…ampbell

This file was added about the same time when non-unified builds were enabled
for all of js/src, so by accident it didn't get updated to work outside of
unified builds. (Non-unified builds are needed to produce correct IWYU results.)

Differential Revision: https://phabricator.services.mozilla.com/D131921

js/src/util/moz.build

@@ -37,5 +37,3 @@ SOURCES += [
 # Suppress warnings in third-party code.
 if CONFIG["CC_TYPE"] in ("clang", "gcc"):
     SOURCES["DoubleToString.cpp"].flags += ["-Wno-implicit-fallthrough"]
-
-REQUIRES_UNIFIED_BUILD = True