Upstream ios/web/web_state/ui support classes

ios/web/web_state/ui/crw_context_menu_provider.mm

Index: ios/web/web_state/ui/crw_context_menu_provider.mm
diff --git a/ios/web/web_state/ui/crw_context_menu_provider.mm b/ios/web/web_state/ui/crw_context_menu_provider.mm
new file mode 100644
index 0000000000000000000000000000000000000000..d11b5b4a2add384d244c25ef65172f44a9eb37a2
--- /dev/null
+++ b/ios/web/web_state/ui/crw_context_menu_provider.mm
@@ -0,0 +1,14 @@
+// Copyright 2014 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/web_state/ui/crw_context_menu_provider.h"
+
+namespace web {
+
+NSString* const kContextTitle = @"ContextTitle";
+NSString* const kContextLinkURLString = @"ContextLinkURLString";
+NSString* const kContextLinkReferrerPolicy = @"ContextLinkReferrerPolicy";
+NSString* const kContextImageURLString = @"ContextImageUrl";
+
+}  // namespace web