This reverts commit 6d96493b.

* Update version number to 3.7.1

* Update version number in port_def.inc

Signed-off-by: Mickaël Schoentgen <contact@tiger-222.fr>

Undelete python/google/protobuf/pyext/proto2_api_test.proto that was accidentally removed from file_list

* Down integrate to github

* Update version number to 3.7.0

* Add php/releash.sh to Makefile.am

* Make cpp_distcheck exit on fail

* Fix construction of messages using the C++ Python implementation when a map field is passed from one message to another.

* Add a test on message map field construction

* python 3 support

* review comments

* add test

* Collapse code into one

We need to cast to a constant charpointer here.

Signed-off-by: Xiang Dai <764524258@qq.com>

* Update version to 3.7.0

* Update version number for java bom

* Add several fixes for python toolchain

* Fix versin regex

* Make script exit on error

* Fix version regex

* Fix version regex

* Fix version regex

* Fix version regex

* Make test run on the current commit

* Fix test

* Fix test

* Use git to retrieve current commit

* Fix tests

* Fix tests

* Also make linux and mac work on the current commit

* Fix test

* Down-integrate internal changes to github.

* fix python conformance test

* fix csharp conformance test

* add back java map_lite_test.proto's optimize for option

* fix php conformance test

* Rebuild python docker image

* Update docker image

* Change call to build_and_run_docker.sh

* Set up python tests for different versions

* Fix comments

- Avoid using typeid() so that we don't depend on RTTI
- Change internal AP MapData() to MutableMapData() and added
  GetMapData()

* Add kokoro build for python source package

* Use libc++ for xcode 10 (#5303)

The xcode 10 removes the deprecated libstdc++ library. We could set
"MACOSX_DEPLOYMENT_TARGET" to "10.9" to use libc++ instead.

* Add python 3.7 build

* Add build for python 3.7 on linux and windows

* Remove unused source build

* Add comment

* Fix $MACOSX_DEPLOYMENT_TARGET mismatch

* Fix MACOSX_DEPLOYMENT_TARGET mismatch

* Add missing import for sysconfig

* Add missing imports

* fix json_format.ParseDict modifies input

* added unit test

* fix naming