[Autofill] Add UMA timing metrics for requestAutocomplete dialog.

chrome/browser/ui/autofill/autofill_dialog_controller_impl.h

Index: chrome/browser/ui/autofill/autofill_dialog_controller_impl.h
diff --git a/chrome/browser/ui/autofill/autofill_dialog_controller_impl.h b/chrome/browser/ui/autofill/autofill_dialog_controller_impl.h
index d400769a8566db7769b9d83f6bac84b427559ada..f690dc98f13dfeb53dc32f85a6d301910a5306a8 100644
--- a/chrome/browser/ui/autofill/autofill_dialog_controller_impl.h
+++ b/chrome/browser/ui/autofill/autofill_dialog_controller_impl.h
@@ -10,6 +10,8 @@
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/string16.h"
+#include "base/time.h"
+#include "chrome/browser/autofill/autofill_metrics.h"
 #include "chrome/browser/autofill/field_types.h"
 #include "chrome/browser/autofill/form_structure.h"
 #include "chrome/browser/autofill/personal_data_manager.h"
@@ -52,6 +54,7 @@ class AutofillDialogControllerImpl : public AutofillDialogController,
       const FormData& form_structure,
       const GURL& source_url,
       const content::SSLStatus& ssl_status,
+      const AutofillMetrics& metric_logger,
       const base::Callback<void(const FormStructure*)>& callback);
   virtual ~AutofillDialogControllerImpl();
 
@@ -262,6 +265,10 @@ class AutofillDialogControllerImpl : public AutofillDialogController,
   // A NotificationRegistrar for tracking the completion of sign-in.
   content::NotificationRegistrar registrar_;
 
+  // For logging UMA metrics.
+  const base::Time dialog_shown_timestamp_;
+  const AutofillMetrics& metric_logger_;
+
   DISALLOW_COPY_AND_ASSIGN(AutofillDialogControllerImpl);
 };