add mac deps to build artifacts on kokoro

tools/internal_ci/helper_scripts/prepare_build_macos_rc

@@ -45,7 +45,7 @@ sudo pip install virtualenv
 sudo pip install -U six tox setuptools
 
 # python 3.4
-wget https://www.python.org/ftp/python/3.4.4/python-3.4.4-macosx10.6.pkg
+wget -q https://www.python.org/ftp/python/3.4.4/python-3.4.4-macosx10.6.pkg
 sudo installer -pkg python-3.4.4-macosx10.6.pkg -target /
 
 git submodule update --init

tools/internal_ci/macos/grpc_build_artifacts.sh

@@ -18,6 +18,24 @@ set -ex
 # change to grpc repo root
 cd $(dirname $0)/../../..
 
-git submodule update --init
+source tools/internal_ci/helper_scripts/prepare_build_macos_rc
+
+# python 3.5
+wget -q https://www.python.org/ftp/python/3.5.2/python-3.5.2-macosx10.6.pkg
+sudo installer -pkg python-3.5.2-macosx10.6.pkg -target /
+
+# install cython for all python versions
+python2.7 -m pip install cython setuptools wheel
+python3.4 -m pip install cython setuptools wheel
+python3.5 -m pip install cython setuptools wheel
+python3.6 -m pip install cython setuptools wheel
+
+# node-gyp (needed for node artifacts)
+npm install -g node-gyp
+
+# php dependencies: pecl
+curl -O http://pear.php.net/go-pear.phar
+sudo php -d detect_unicode=0 go-pear.phar
+
 
 tools/run_tests/task_runner.py -f artifact macos