media: Invoke PlatformVerificationDialog from ProtectedMediaIdentifierPermissionContext.

chrome/browser/chromeos/attestation/platform_verification_dialog.h

Index: chrome/browser/chromeos/attestation/platform_verification_dialog.h
diff --git a/chrome/browser/chromeos/attestation/platform_verification_dialog.h b/chrome/browser/chromeos/attestation/platform_verification_dialog.h
index e33ebd0e9fd2f4255158f7c7e9b3059b196074aa..2dd6e2f9c39686fab7ee8c063abdd41300658257 100644
--- a/chrome/browser/chromeos/attestation/platform_verification_dialog.h
+++ b/chrome/browser/chromeos/attestation/platform_verification_dialog.h
@@ -26,8 +26,12 @@ class PlatformVerificationDialog : public views::DialogDelegateView,
                                    public content::WebContentsObserver {
  public:
   // Initializes a tab-modal dialog for |web_contents| and shows it.
-  static void ShowDialog(
+  // Returns a non-owning pointer to the widget so that caller can close the
+  // dialog and cancel the request. The returned widget is only guaranteed to be
+  // valid before |callback| is called.
+  static views::Widget* ShowDialog(
       content::WebContents* web_contents,
+      const GURL& requesting_origin,

[Darren Krahn, 2015/02/05 16:40:44]

nit: undocumented arg

Also, this means the dialog can display something to the user that is different
than the WebContents acting as the dialog parent. This seems misleading.

[xhwang, 2015/02/05 18:09:48]

Done.
hmm, this is consistent with how permission bubble/infobar works. After all it's
|requesting_origin| requesting the permission, and |requesting_origin| can be
very different from the url of the |web_contents|.

       const PlatformVerificationFlow::Delegate::ConsentCallback& callback);
 
  protected: