[ios] Implemented iOS analogue of SSLErrorHandler class.

ios/chrome/browser/ssl/ios_ssl_error_handler.h

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef IOS_CHROME_BROWSER_SSL_IOS_SSL_ERROR_HANDLER_H_
+#define IOS_CHROME_BROWSER_SSL_IOS_SSL_ERROR_HANDLER_H_
+
+#include "base/callback.h"

[sdefresne, 2016/06/30 11:58:16]

Can you instead include "base/callback_forward.h"? It should be enough for the
header file (you'll need the include of "base/callback.h" in the implementation
and the implementation of client code).

[Eugene But (OOO till 7-30), 2016/06/30 18:35:57]

Done.

+#include "url/gurl.h"
+
+namespace net {
+class SSLInfo;
+}  // namespace net
+
+namespace web {
+class WebState;
+}  // namespace web
+
+// This class is responsible for deciding what type of interstitial to show for
+// an SSL validation error.
+class IOSSSLErrorHandler {
+ public:
+  // Entry point for the class.
+  static void HandleSSLError(web::WebState* web_state,
+                             int cert_error,
+                             const net::SSLInfo& info,
+                             const GURL& request_url,
+                             bool overridable,
+                             const base::Callback<void(bool)>& callback);
+
+ private:
+  IOSSSLErrorHandler();

[sdefresne, 2016/06/30 11:58:16]

It looks like this class only has static method, so why not mark it as non
constructible using DISALLOW_IMPLICIT_CONSTRUCTORS? Then you don't even have to
provide implementation for the constructor in the implementation file. You may
have to delete the destructor too:

~IOSSSLErrorHandler() = delete;

[Eugene But (OOO till 7-30), 2016/06/30 18:35:57]

Done.

+  ~IOSSSLErrorHandler();
+  // Called on SSL interstitial dismissal.
+  static void InterstitialWasDismissed(
+      web::WebState* web_state,
+      const base::Callback<void(bool)>& callback,
+      bool proceed);
+};
+
+#endif  // IOS_CHROME_BROWSER_SSL_IOS_SSL_ERROR_HANDLER_H_