Using native sheet to display modal dialogs for sign in

chrome/browser/ui/signin_view_controller_delegate.h

Index: chrome/browser/ui/signin_view_controller_delegate.h
diff --git a/chrome/browser/ui/signin_view_controller_delegate.h b/chrome/browser/ui/signin_view_controller_delegate.h
index 6f9de730afaa68b05ed917bc8a88e0dbd49901a1..7b514d005f3bf6a30cc76725dc16613c9f0bda39 100644
--- a/chrome/browser/ui/signin_view_controller_delegate.h
+++ b/chrome/browser/ui/signin_view_controller_delegate.h
@@ -46,10 +46,13 @@ class SigninViewControllerDelegate : public content::WebContentsDelegate {
       SigninViewController* signin_view_controller,
       Browser* browser);
 
+  // Closes the Sign in dialog. The instance should be considered has being
+  // destroyed.
   void CloseModalSignin();

[msarda, 2017/01/10 15:58:43]

There is a typo in this comment: "the instance should be considered has being
destroyed."

I would change this comment and the ones below as the following:
"Closes the sign-in dialog. Note that this method may destroy this object,
so the caller should no longer use this object after calling this method."

[jlebel, 2017/01/11 14:25:24]

Done.

 
   // Either navigates back in the signin flow if the history state allows it or
-  // closes the flow otherwise.
+  // closes the flow otherwise. If view is closed, the instance should be
+  // considered has being destroyed.
   void PerformNavigation();
 
   // This will be called by the base class to request a resize of the native
@@ -65,6 +68,17 @@ class SigninViewControllerDelegate : public content::WebContentsDelegate {
   content::WebContents* web_contents_for_testing() { return web_contents_; }
 
  protected:
+  // The presentation type of the modal sign-in dialog.
+  enum DialogModalType {
+    // The sign-in dialog is presented as tab modal: the user may interact with
+    // the parent window and the dialog is dismissed on tab navigation.
+    TAB_MODAL,
+
+    // The sign-in dialog is presented as window modal: the user cannot interact
+    // with the parent window an
+    WINDOW_MODAL
+  };
+
   SigninViewControllerDelegate(SigninViewController* signin_view_controller,
                                content::WebContents* web_contents);
   ~SigninViewControllerDelegate() override;
@@ -78,7 +92,8 @@ class SigninViewControllerDelegate : public content::WebContentsDelegate {
 
   // This will be called by this base class when the tab-modal window must be
   // closed. This should close the platform-specific window that is currently
-  // showing the sign in flow or the sync confirmation dialog.
+  // showing the sign in flow or the sync confirmation dialog. After this call,
+  // the current instance should be considered has being destroyed.
   virtual void PerformClose() = 0;
 
  private: