Add some basic success/failure UMA logging for autofill.

chrome/browser/autofill/autofill_download.cc

Index: chrome/browser/autofill/autofill_download.cc
diff --git a/chrome/browser/autofill/autofill_download.cc b/chrome/browser/autofill/autofill_download.cc
index 9b2e747ccc0f839dd9cadd821fa5d8c9fc9793a2..f60d3ba87e260e959572892a3f8bba949c9f3e2a 100644
--- a/chrome/browser/autofill/autofill_download.cc
+++ b/chrome/browser/autofill/autofill_download.cc
@@ -67,7 +67,8 @@ void AutoFillDownloadManager::SetObserver(
 }
 
 bool AutoFillDownloadManager::StartQueryRequest(
-    const ScopedVector<FormStructure>& forms) {
+    const ScopedVector<FormStructure>& forms,
+    autofill_metrics::LogServerQueryMetricFn log_server_query_metric) {
   if (next_query_request_ > base::Time::Now()) {
     // We are in back-off mode: do not do the request.
     return false;
@@ -79,7 +80,7 @@ bool AutoFillDownloadManager::StartQueryRequest(
     return false;
 
   request_data.request_type = AutoFillDownloadManager::REQUEST_QUERY;
-  autofill_metrics::LogServerQueryMetric(autofill_metrics::QUERY_SENT);
+  log_server_query_metric(autofill_metrics::QUERY_SENT);
 
   return StartRequest(form_xml, request_data);
 }