mojo: remove need for ShellTestBase::InitMojo

ChildProcessTest is really just a unit test, so can use testing::Test directly.

BUG=

Review URL: https://codereview.chromium.org/343843002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@279503 0039d316-1c4b-4281-b951-d872f2087c98
4 files changed