Refactor client cert private key handling.

chrome/browser/ui/crypto_module_delegate_nss.h

Index: chrome/browser/ui/crypto_module_delegate_nss.h
diff --git a/chrome/browser/ui/crypto_module_delegate_nss.h b/chrome/browser/ui/crypto_module_delegate_nss.h
index 45029f8b7c057f7f4cadc05652c01867c4565f3f..f5f9282618a59bc64e1c959459e992e609a4b12b 100644
--- a/chrome/browser/ui/crypto_module_delegate_nss.h
+++ b/chrome/browser/ui/crypto_module_delegate_nss.h
@@ -31,8 +31,6 @@ class ChromeNSSCryptoModuleDelegate
                                 const net::HostPortPair& server,
                                 crypto::ScopedPK11Slot slot);
 
-  ~ChromeNSSCryptoModuleDelegate() override;
-
   // Must be called on IO thread. Creates a delegate and returns it
   // synchronously or asynchronously to |callback|. If the delegate could not be
   // created, |callback| is called with NULL.
@@ -40,8 +38,8 @@ class ChromeNSSCryptoModuleDelegate
       chrome::CryptoModulePasswordReason reason,
       const net::HostPortPair& server,
       content::ResourceContext* context,
-      const base::Callback<
-          void(std::unique_ptr<ChromeNSSCryptoModuleDelegate>)>& callback);
+      const base::Callback<void(scoped_refptr<ChromeNSSCryptoModuleDelegate>)>&
+          callback);
 
   // crypto::NSSCryptoModuleDelegate implementation.
   crypto::ScopedPK11Slot RequestSlot() override;
@@ -52,6 +50,10 @@ class ChromeNSSCryptoModuleDelegate
                               bool* cancelled) override;
 
  private:
+  friend class base::RefCountedThreadSafe<ChromeNSSCryptoModuleDelegate>;
+
+  ~ChromeNSSCryptoModuleDelegate() override;
+
   void ShowDialog(const std::string& slot_name, bool retry);
 
   void GotPassword(const std::string& password);