python: update to 2.7.10 [reland]

New ebuild is derived from Gentoo's 2.7.10 ebuild by copying
ChromiumOS-specific changes from the old ebuild and adapting
ChrmiumOS-specific patches.

The new depot_tools update has landed and seems to be stable,
so we should be able to land this now too.

BUG=b:22248294
TEST=Trybot succeeded on chromiumos-sdk, arm-generic, x86-generic and amd64-generic.

Change-Id: I67852de865a386415ae3698853d4ff557e99c88d
Reviewed-on: https://chromium-review.googlesource.com/313800
Commit-Ready: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Andrey Ulanov <andreyu@google.com>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
diff --git a/dev-lang/python/files/python-2.7.5-nonfatal-compileall.patch b/dev-lang/python/files/python-2.7.5-nonfatal-compileall.patch
new file mode 100644
index 0000000..a762dfb
--- /dev/null
+++ b/dev-lang/python/files/python-2.7.5-nonfatal-compileall.patch
@@ -0,0 +1,18 @@
+diff --git a/Makefile.pre.in b/Makefile.pre.in
+--- a/Makefile.pre.in
++++ b/Makefile.pre.in
+@@ -1000,12 +1000,12 @@
+ 		$(INSTALL_DATA) $(srcdir)/Modules/xxmodule.c \
+ 			$(DESTDIR)$(LIBDEST)/distutils/tests ; \
+ 	fi
+-	PYTHONPATH=$(DESTDIR)$(LIBDEST)  $(RUNSHARED) \
++	-PYTHONPATH=$(DESTDIR)$(LIBDEST)  $(RUNSHARED) \
+ 		$(PYTHON_FOR_BUILD) -Wi -tt $(DESTDIR)$(LIBDEST)/compileall.py \
+ 		-d $(LIBDEST) -f \
+ 		-x 'bad_coding|badsyntax|site-packages|lib2to3/tests/data' \
+ 		$(DESTDIR)$(LIBDEST)
+-	PYTHONPATH=$(DESTDIR)$(LIBDEST) $(RUNSHARED) \
++	-PYTHONPATH=$(DESTDIR)$(LIBDEST) $(RUNSHARED) \
+ 		$(PYTHON_FOR_BUILD) -Wi -tt -O $(DESTDIR)$(LIBDEST)/compileall.py \
+ 		-d $(LIBDEST) -f \
+ 		-x 'bad_coding|badsyntax|site-packages|lib2to3/tests/data' \