Merged from https://widevine-internal-review.googlesource.com/165861 We want debug headers to help diagnose b/186031735. I also saw that we were only logging the domain name for some errors instead of the full URL. Bug: 186031735 Test: GtsMediaTestCases Change-Id: I4d469a73e54f86d4d3b5d50bd0030fdb2a36df50