Install the installer built by RepackTemplates.

def _InstallInstallers(self):
    """Install the installer built by RepackTemplates."""
    # 32 bit binary will refuse to install on a 64bit system so we only install
    # the 64 bit version
    installer_amd64 = glob.glob(
        os.path.join(args.output_dir, "dbg_*_amd64.exe")).pop()
    self._CleanupInstall()
    # The exit code is always 0, test to see if install was actually successful.
    subprocess.check_call([installer_amd64])
    self._CheckInstallSuccess()