Implement newly designed sign-in related histograms for desktop platorms.

chrome/browser/ui/views/profiles/signin_view_controller.h

Index: chrome/browser/ui/views/profiles/signin_view_controller.h
diff --git a/chrome/browser/ui/views/profiles/signin_view_controller.h b/chrome/browser/ui/views/profiles/signin_view_controller.h
index 668be1489e9e2141e059bb48dbfbc618742a1d76..29d8fd9c65d844c6764df03eaf8b34dfa7fc04c0 100644
--- a/chrome/browser/ui/views/profiles/signin_view_controller.h
+++ b/chrome/browser/ui/views/profiles/signin_view_controller.h
@@ -8,6 +8,7 @@
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "chrome/browser/ui/profile_chooser_constants.h"
+#include "components/signin/core/browser/signin_metrics.h"
 
 class Browser;
 class ModalSigninDelegate;
@@ -35,11 +36,16 @@ class SigninViewController {
   static views::WebView* CreateGaiaWebView(
       content::WebContentsDelegate* delegate,
       profiles::BubbleViewMode mode,
-      Profile* profile);
+      Profile* profile,
+      signin_metrics::AccessPoint access_point);
 
   // Shows the signin flow as a tab modal dialog attached to |browser|'s active
   // web contents.
-  void ShowModalSignin(profiles::BubbleViewMode mode, Browser* browser);
+  // |access_point| indicates the access point used to open the Gaia sign in
+  // page.
+  void ShowModalSignin(profiles::BubbleViewMode mode,
+                       Browser* browser,
+                       signin_metrics::AccessPoint access_point);
 
   // Closes the tab-modal signin flow previously shown using this
   // SigninViewController, if one exists. Does nothing otherwise.