Add window open and close delegate methods to CWVUIDelegate.

ios/web_view/internal/cwv_navigation_action.mm

Index: ios/web_view/internal/cwv_navigation_action.mm
diff --git a/ios/web_view/internal/cwv_navigation_action.mm b/ios/web_view/internal/cwv_navigation_action.mm
new file mode 100644
index 0000000000000000000000000000000000000000..fc0731c6eeddfc0d9cefd2d1fe4196a969b7e16e
--- /dev/null
+++ b/ios/web_view/internal/cwv_navigation_action.mm
@@ -0,0 +1,25 @@
+// Copyright 2017 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.
+
+#import "ios/web_view/public/cwv_navigation_action.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+@implementation CWVNavigationAction
+@synthesize request = _request;
+@synthesize userInitiated = _userInitiated;
+
+- (instancetype)initWithRequest:(NSURLRequest*)request
+                  userInitiated:(BOOL)userInitiated {
+  self = [super init];
+  if (self) {
+    _userInitiated = userInitiated;
+    _request = [request copy];
+  }
+  return self;
+}
+
+@end