https://bugs.webkit.org/show_bug.cgi?id=76935

Reviewed by Ryosuke Niwa.

Extend the WinPort class with commands to set and clean up various registry
values needed to invoke the correct debugger to get crash files.

* Scripts/webkitpy/port/win.py:
(WinPort): Added global caches for registry keys and settings
(WinPort._ntsd_location): Added
(WinPort.create_debugger_command_file): Added
(WinPort.read_registry_string): Added
(WinPort.write_registry_string): Added
(WinPort.setup_crash_log_saving): Added
(WinPort.restore_crash_log_saving): Added
(WinPort.setup_test_run): Added overload to add registry settings.
(WinPort.clean_up_test_run): Added overload to clean up registry settings.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@151004 268f45cc-cd09-0410-ab3c-d52691b4dbfc