UPSTREAM: dev-lang/python: Backport gcc[-libffi(-)] blocker fix to all versions

Cherry-picked from 58a659534b0c077698dff2ff33bb568e124d96bc
Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>

BUG=chromium:736313
TEST=PreCQ and SDK tryjob

Change-Id: I3b701bcc8b5b5c8fe8c839665434bf774bd9af89
Reviewed-on: https://chromium-review.googlesource.com/1627118
Commit-Ready: Daniel Kurtz <djkurtz@chromium.org>
Tested-by: Daniel Kurtz <djkurtz@chromium.org>
Legacy-Commit-Queue: Commit Bot <commit-bot@chromium.org>
Reviewed-by: Chris McDonald <cjmcdonald@chromium.org>
diff --git a/dev-lang/python/python-2.7.10.ebuild b/dev-lang/python/python-2.7.10.ebuild
index 6cf1b06..dc8bc43 100644
--- a/dev-lang/python/python-2.7.10.ebuild
+++ b/dev-lang/python/python-2.7.10.ebuild
@@ -78,7 +78,7 @@
 DEPEND="${RDEPEND}
 	virtual/pkgconfig
 	>=sys-devel/autoconf-2.65
-	!sys-devel/gcc[libffi]"
+	!sys-devel/gcc[libffi(-)]"
 RDEPEND+=" !build? ( app-misc/mime-types )
 	doc? ( dev-python/python-docs:${SLOT} )"
 PDEPEND=">=app-eselect/eselect-python-20140125-r1"