Merge pull request #5384 from ctiller/44

Makefile

build.yaml

src/core/support/env_linux.c

templates/Makefile.template

...tools/dockerfile/test/cxx_squeeze_x64/Dockerfile.template

...ockerfile/test/cxx_squeeze_x64/post-git-setup.sh.template

templates/tools/openssl/use_openssl.sh.template

test/build/boringssl.c

test/build/shadow.c

tools/dockerfile/test/cxx_squeeze_x64/Dockerfile

tools/dockerfile/test/cxx_squeeze_x64/post-git-setup.sh

tools/jenkins/docker_run.sh

tools/jenkins/docker_run_tests.sh

tools/openssl/use_openssl.sh