[autotest]: Refactor bug filing.

This creates a new Bug class that TestFailure now derives from. This allows us
to file bugs for issues that are not test failures.

BUG=chromium:254256
TEST=Unit tests and ran the dummy suite and saw that the tests were deduped.

Change-Id: I104489e9627a64506fc9c206392f1297fa538c44
Reviewed-on: https://gerrit.chromium.org/gerrit/65898
Reviewed-by: Prashanth Balasubramanian <beeps@chromium.org>
Reviewed-by: Keyar Hood <keyar@chromium.org>
Tested-by: Keyar Hood <keyar@chromium.org>
Commit-Queue: Keyar Hood <keyar@chromium.org>
diff --git a/global_config.ini b/global_config.ini
index e618a5d..85f7b39 100644
--- a/global_config.ini
+++ b/global_config.ini
@@ -193,6 +193,8 @@
 build_prefix: build/
 tracker_url: https://code.google.com/p/chromium/issues/detail?id=
 gs_file_prefix: gs://
+chromium_email_address = @chromium.org
+test_failure_owner = beeps@chromium.org
 credentials: USE SHADOW CREDENTIALS