Add Net.HttpAuthCount histogram to track failure rate per authentication scheme.

This suffers from a few potential issues, stemming from the lack of feedback of whether an authentication attempt succeeded.
  - It will count failures from preemptive authentication but not preemptive authentication attempts.
  - It will count challenges which do not result in Authorize headers being sent back up (UrlFetcher requests before HttpAuthCache is populated, user canceling an auth attempt).

Still, it seems better than having no insight right now. If it's too noisy I'll look at ways to improve it.

BUG=57628
TEST=Manually verified that histogram counts worked.

Review URL: http://codereview.chromium.org/3590012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@62158 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 3 insertions, 1 deletions

diff --git a/net/http/http_auth_controller.h b/net/http/http_auth_controller.h
index 097c4bc..bcda707 100644
--- a/net/http/http_auth_controller.h
+++ b/net/http/http_auth_controller.h
@@ -10,6 +10,7 @@
 #include <string>
 
 #include "base/basictypes.h"
+#include "base/non_thread_safe.h"
 #include "base/ref_counted.h"
 #include "base/scoped_ptr.h"
 #include "base/string16.h"
@@ -27,7 +28,8 @@ class HttpAuthCache;
 class HttpRequestHeaders;
 struct HttpRequestInfo;
 
-class HttpAuthController : public base::RefCounted<HttpAuthController> {
+class HttpAuthController : public base::RefCounted<HttpAuthController>,
+                           public NonThreadSafe {
  public:
   // The arguments are self explanatory except possibly for |auth_url|, which
   // should be both the auth target and auth path in a single url argument.