Revision 1052894

HTTPCLIENT-1035: committed validating acceptance test and wired in new
cache invalidation call. Also cleaned up some unit tests in
TestCachingHttpClient: static imports of EasyMock methods, as well as
removing unit tests that exercised some protected methods, especially
where they are already covered by acceptance tests against a public
interface (unit testing protected methods leads to brittle tests). Also
rewrite some of the unit tests in TestCachingHttpClient to depend on
fewer mocks (often, just a mock backend HttpClient and mock cache
storage).