fixup! Base Browser's .mozconfigs.

Bug 42035: Update mozconfig for macos development

mozconfig-macos-dev

+. $topsrcdir/browser/config/mozconfigs/base-browser
+
+# This mozconfig file is not used in official builds.
+# It is only intended to be used when doing incremental macOS builds
+# during development.
+
+export MOZILLA_OFFICIAL=
+
+ac_add_options --disable-strip
+ac_add_options --disable-install-strip
+
+ac_add_options --with-base-browser-version=dev-build
+
+ac_add_options --disable-base-browser-update
+# See bug #13379
+ac_add_options --enable-nss-mar
+# See bug #41131
+ac_add_options --disable-update-agent
+