Revert 252714 "Add some handle read/write helpers to mojo/common..."

> Add some handle read/write helpers to mojo/common/test/test_utils.h
> 
> This helps to refactor raw_channel_posix_unittest to run on multiple
> platforms.
> 
> TEST=mojo_common_unittests,mojo_system_unittests
> BUG=None
> R=viettrungluu@chromium.org
> 
> Review URL: https://codereview.chromium.org/172263006

TBR=yzshen@chromium.org

Review URL: https://codereview.chromium.org/175703004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252718 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252718