[Autofill] Add UMA timing metrics for requestAutocomplete dialog.

chrome/browser/autofill/autofill_manager_delegate.h

Index: chrome/browser/autofill/autofill_manager_delegate.h
diff --git a/chrome/browser/autofill/autofill_manager_delegate.h b/chrome/browser/autofill/autofill_manager_delegate.h
index 019f36d53d14a6457a636cc6c0ced199cc9694d8..e28e6b36af5fd8a82d4168beaed898158178526e 100644
--- a/chrome/browser/autofill/autofill_manager_delegate.h
+++ b/chrome/browser/autofill/autofill_manager_delegate.h
@@ -21,6 +21,7 @@ namespace gfx {
 class Rect;
 }
 
+class AutofillMetrics;
 class FormStructure;
 class GURL;
 class InfoBarService;
@@ -83,6 +84,7 @@ class AutofillManagerDelegate {
       const FormData& form,
       const GURL& source_url,
       const content::SSLStatus& ssl_status,
+      const AutofillMetrics& metric_logger,
       const base::Callback<void(const FormStructure*)>& callback) = 0;
 
   // Called when the dialog for request autocomplete closes.