Coin: Log files are not accessible

I sent an early draft of [0] to Coin for an early warning build-and-test; the draft contained only the new regression test, as I wanted to verify the bug actually exists - I was expecting a failure on MS-Windows.

• [0] https://codereview.qt-project.org/#/c/206938/
• [1] http://coin.intra.qt.io/coin/integration/qt/qtbase/tasks/web_qt_qtbase_1506518003030

The test results are all green, but every MS-Windows platform's part of the results lacks results; I click on the "Raw log" link for Test on any of these platforms and get 404'd.