Update to latest wptrunner.
Update web-platform-tests to revision 6dc0391257a1666a90f66c8da193b43cd9c60dcb

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rename : testing/web-platform/tests/proximity/ProximityEvent_tests.html => testing/web-platform/tests/proximity/DeviceProximityEvent_tests.html
rename : testing/web-platform/tests/proximity/ProximityEvent_tests.html => testing/web-platform/tests/proximity/UserProximityEvent_tests.html