[ios] Implemented iOS analogue of SSLErrorHandler class.

ios/chrome/browser/ssl/ios_ssl_error_handler_unittest.mm

+// 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.
+
+#include "ios/chrome/browser/ssl/ios_ssl_error_handler.h"
+
+#include "base/mac/bind_objc_block.h"
+#include "ios/chrome/browser/browser_state/test_chrome_browser_state.h"
+#include "ios/web/public/interstitials/web_interstitial.h"
+#import "ios/web/public/test/web_test_with_web_state.h"
+#import "ios/web/public/web_state/web_state.h"
+#include "net/ssl/ssl_info.h"
+#include "net/test/cert_test_util.h"
+#include "net/test/test_data_directory.h"
+
+namespace {
+// Test cert filename.

[estark, 2016/06/29 23:00:15]

nit: I would just name these |kTestCertFileName| and |kTestHostName| and omit
the comments. (Or even just leave the names as they are and you could still omit
the comments IMO.)

[Eugene But (OOO till 7-30), 2016/06/30 00:05:26]

Done.

+const char kCertFileName[] = "ok_cert.pem";
+// Test hostname.
+const char kHostName[] = "https://chromium.test/";
+}  // namespace
+
+// Test fixture for IOSSSLErrorHandler class.
+class IOSSSLErrorHandlerTest : public web::WebTestWithWebState {
+ protected:
+  IOSSSLErrorHandlerTest()
+      : browser_state_(builder_.Build()),
+        cert_(net::ImportCertFromFile(net::GetTestCertsDirectory(),
+                                      kCertFileName)) {}
+
+  // web::WebTestWithWebState overrides:
+  void SetUp() override {
+    web::WebTestWithWebState::SetUp();
+    ASSERT_TRUE(cert_);
+    ASSERT_FALSE(web_state()->IsShowingWebInterstitial());
+  }
+  web::BrowserState* GetBrowserState() override { return browser_state_.get(); }
+
+  // Returns certificate for testing.
+  scoped_refptr<net::X509Certificate> cert() { return cert_; }
+
+ private:
+  TestChromeBrowserState::Builder builder_;
+  std::unique_ptr<TestChromeBrowserState> browser_state_;
+  scoped_refptr<net::X509Certificate> cert_;
+};
+
+// Tests non-overridable error handling.
+TEST_F(IOSSSLErrorHandlerTest, NonOverridable) {
+  net::SSLInfo ssl_info;
+  ssl_info.cert = cert();
+  GURL url(kHostName);
+  __block bool do_not_proceed_callback_called = false;
+  IOSSSLErrorHandler::HandleSSLError(
+      web_state(), net::ERR_CERT_AUTHORITY_INVALID, ssl_info, url, false,
+      base::BindBlock(^(bool proceed) {
+        EXPECT_FALSE(proceed);
+        do_not_proceed_callback_called = true;
+      }));
+
+  // Make sure that interstitial is displayed.
+  EXPECT_TRUE(web_state()->IsShowingWebInterstitial());
+  web::WebInterstitial* interstitial = web_state()->GetWebInterstitial();
+  EXPECT_TRUE(interstitial);
+
+  // Make sure callback is called on dismissal.
+  interstitial->DontProceed();
+  EXPECT_TRUE(do_not_proceed_callback_called);
+}
+
+// Tests overridable error handling.
+TEST_F(IOSSSLErrorHandlerTest, Overridable) {
+  net::SSLInfo ssl_info;
+  ssl_info.cert = cert();
+  GURL url(kHostName);
+  __block bool proceed_callback_called = false;
+  IOSSSLErrorHandler::HandleSSLError(
+      web_state(), net::ERR_CERT_AUTHORITY_INVALID, ssl_info, url, true,
+      base::BindBlock(^(bool proceed) {
+        EXPECT_TRUE(proceed);
+        proceed_callback_called = true;
+      }));
+
+  // Make sure that interstitial is displayed.
+  EXPECT_TRUE(web_state()->IsShowingWebInterstitial());
+  web::WebInterstitial* interstitial = web_state()->GetWebInterstitial();
+  EXPECT_TRUE(interstitial);
+
+  // Make sure callback is called on dismissal.
+  interstitial->Proceed();
+  EXPECT_TRUE(proceed_callback_called);

[estark, 2016/06/29 23:00:15]

optional additional test: you could test that DontProceed() also calls the
callback for overridable errors.

[Eugene But (OOO till 7-30), 2016/06/30 00:05:26]

Done. Let me know if you think that I should also address code duplication.
Personally I think it's ok to have them in tests for clarity.

+}