Add a NavigationThrottle to the public content/ interface

components/navigation_interception/intercept_navigation_throttle.cc

Index: components/navigation_interception/intercept_navigation_throttle.cc
diff --git a/components/navigation_interception/intercept_navigation_throttle.cc b/components/navigation_interception/intercept_navigation_throttle.cc
new file mode 100644
index 0000000000000000000000000000000000000000..84c5f9b9edfb72fc47cbcef2b136e059c40918cc
--- /dev/null
+++ b/components/navigation_interception/intercept_navigation_throttle.cc
@@ -0,0 +1,45 @@
+// Copyright 2015 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 "components/navigation_interception/intercept_navigation_throttle.h"
+
+#include "components/navigation_interception/navigation_params.h"
+#include "content/public/browser/navigation_handle.h"
+
+namespace navigation_interception {
+
+InterceptNavigationThrottle::InterceptNavigationThrottle(
+    content::NavigationHandle* navigation_handle,
+    CheckCallback should_ignore_callback)
+    : content::NavigationThrottle(navigation_handle),
+      should_ignore_callback_(should_ignore_callback) {}
+
+InterceptNavigationThrottle::~InterceptNavigationThrottle() {}
+
+content::NavigationThrottle::ThrottleCheckResult
+InterceptNavigationThrottle::WillStartRequest() {
+  return CheckIfShouldIgnoreNavigation(false);
+}
+
+content::NavigationThrottle::ThrottleCheckResult
+InterceptNavigationThrottle::WillRedirectRequest() {
+  return CheckIfShouldIgnoreNavigation(true);
+}
+
+content::NavigationThrottle::ThrottleCheckResult
+InterceptNavigationThrottle::CheckIfShouldIgnoreNavigation(bool is_redirect) {
+  NavigationParams navigation_params(
+      navigation_handle()->GetValidatedURL(),
+      navigation_handle()->GetReferrer(), navigation_handle()->HasUserGesture(),
+      navigation_handle()->IsPost(), navigation_handle()->GetPageTransition(),
+      is_redirect, navigation_handle()->IsExternalProtocol(), true);
+
+  bool should_ignore_navigation = should_ignore_callback_.Run(
+      navigation_handle()->GetWebContents(), navigation_params);
+  return should_ignore_navigation
+             ? content::NavigationThrottle::CANCEL_AND_IGNORE
+             : content::NavigationThrottle::PROCEED;
+}
+
+}  // namespace navigation_interception