[content-security-policy-tests] Try to make the CSP tests a bit more stable, (#1707)

Increase the test timeout for some problematic tests. Ensure that the
report check returns early when a report is detected as expected.

Upstreamed from https://bugzilla.mozilla.org/show_bug.cgi?id=1124091

View on GitHub: https://github.com/w3c/web-platform-tests/pull/1707

Received on Thursday, 2 April 2015 13:21:31 UTC