Add "Sign In" button to the account chooser on Mac.

chrome/browser/ui/passwords/password_dialog_controller.h

Index: chrome/browser/ui/passwords/password_dialog_controller.h
diff --git a/chrome/browser/ui/passwords/password_dialog_controller.h b/chrome/browser/ui/passwords/password_dialog_controller.h
index 02b0fc447f2a57ee80a125501947f452a8e02f56..3f3854de554bd314cc49e17b3fafbba3f4d4f2ed 100644
--- a/chrome/browser/ui/passwords/password_dialog_controller.h
+++ b/chrome/browser/ui/passwords/password_dialog_controller.h
@@ -34,6 +34,9 @@ class PasswordDialogController {
   virtual std::pair<base::string16, gfx::Range> GetAccoutChooserTitle() const
       = 0;
 
+  // Whether the account chooser should display the "Sign in" button.
+  virtual bool ShouldShowSignInButton() const = 0;
+
   // Returns the title for the autosignin first run dialog.
   virtual base::string16 GetAutoSigninPromoTitle() const = 0;
 
@@ -49,6 +52,9 @@ class PasswordDialogController {
       const autofill::PasswordForm& password_form,
       password_manager::CredentialType credential_type) = 0;
 
+  // Called when the user clicks "Sign in" in the account chooser.
+  virtual void OnSignInClicked() = 0;
+
   // Called when user clicks OK in the auto signin first run promo.
   virtual void OnAutoSigninOK() = 0;