Add functions to autoinstaller needed for Benchmark Runner script

Add functions to autoinstaller needed for Benchmark Runner script
https://bugs.webkit.org/show_bug.cgi?id=174331

Patch by Matthew Stewart <matthew_r_stewart@apple.com> on 2017-07-24
Reviewed by Dean Johnson, Dewei Zhu, Stephanie Lewis.

Adds autoinstaller functions to install selenium and webdriver binaries
which will be used by the browser driver part of Benchmark Runner.

* Scripts/webkitpy/benchmark_runner/browser_driver/browser_driver.py:
(BrowserDriver.restore_env):
(BrowserDriver):
(BrowserDriver.get_webdriver_binary_path):
* Scripts/webkitpy/benchmark_runner/browser_driver/linux_chrome_driver.py:
(LinuxChromeDriver.launch_driver):
* Scripts/webkitpy/benchmark_runner/browser_driver/linux_firefox_driver.py:
(LinuxFirefoxDriver.launch_driver):
* Scripts/webkitpy/benchmark_runner/browser_driver/osx_chrome_driver.py:
(OSXChromeDriver.launch_driver):
(OSXChromeCanaryDriver.launch_driver):
* Scripts/webkitpy/benchmark_runner/browser_driver/osx_firefox_driver.py:
(OSXFirefoxDriver.launch_driver):
(OSXFirefoxNightlyDriver.launch_driver):
* Scripts/webkitpy/benchmark_runner/browser_driver/osx_safari_driver.py:
* Scripts/webkitpy/benchmark_runner/utils.py:
(get_driver_binary_path):
* Scripts/webkitpy/common/system/autoinstall.py:
(AutoInstaller._unzip):
* Scripts/webkitpy/thirdparty/__init__.py:
(AutoinstallImportHook.find_module):
(AutoinstallImportHook._install_selenium):
(AutoinstallImportHook):
(AutoinstallImportHook._install_chromedriver):
(AutoinstallImportHook._install_geckodriver):
(AutoinstallImportHook.get_latest_pypi_url):
(AutoinstallImportHook.install_binary):
(autoinstall_everything):
(get_driver_filename):
(get_os_info):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@219853 268f45cc-cd09-0410-ab3c-d52691b4dbfc