Histogram how often IDENT_SRC_URL is used.

net/http/http_auth_controller.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/http/http_auth_controller.h"
 
 #include "base/metrics/histogram.h"
 #include "base/string_util.h"
 #include "base/threading/platform_thread.h"
 #include "base/utf_string_conversions.h"
@@ skipping 447 matching lines @@
     identity_.source = HttpAuth::IDENT_SRC_URL;
     identity_.invalid = false;
     // Extract the username:password from the URL.
     string16 username;
     string16 password;
     GetIdentityFromURL(auth_url_, &username, &password);
     identity_.credentials.Set(username, password);
     embedded_identity_used_ = true;
     // TODO(eroman): If the password is blank, should we also try combining
     // with a password from the cache?
+    UMA_HISTOGRAM_BOOLEAN("net.HTTPIdentSrcURL", true);
     return true;
   }
 
   // Check the auth cache for a realm entry.
   HttpAuthCache::Entry* entry =
       http_auth_cache_->Lookup(auth_origin_, handler_->realm(),
                                handler_->auth_scheme());
 
   if (entry) {
     identity_.source = HttpAuth::IDENT_SRC_REALM_LOOKUP;
@@ skipping 80 matching lines @@
   DCHECK(CalledOnValidThread());
   return disabled_schemes_.find(scheme) != disabled_schemes_.end();
 }
 
 void HttpAuthController::DisableAuthScheme(HttpAuth::Scheme scheme) {
   DCHECK(CalledOnValidThread());
   disabled_schemes_.insert(scheme);
 }
 
 }  // namespace net