Introduce WebRequestResourceType.

extensions/browser/api/web_request/web_request_resource_type.h

+// 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.
+
+#ifndef EXTENSIONS_BROWSER_API_WEB_REQUEST_WEB_REQUEST_RESOURCE_TYPE_H_
+#define EXTENSIONS_BROWSER_API_WEB_REQUEST_WEB_REQUEST_RESOURCE_TYPE_H_
+
+#include "content/public/common/resource_type.h"
+
+namespace net {
+class URLRequest;
+}  // namespace net
+
+namespace extensions {
+
+// Enumerates all resource/request types that WebRequest API cares about.
+enum class WebRequestResourceType {
+  // Below are content::ResourceType values. Note: Each content::RESOURCE_TYPE_*
+  // is typed explicitly in order to catch if some of those values get deleted.
+  MAIN_FRAME = content::RESOURCE_TYPE_MAIN_FRAME,
+  SUB_FRAME = content::RESOURCE_TYPE_SUB_FRAME,
+  STYLESHEET = content::RESOURCE_TYPE_STYLESHEET,
+  SCRIPT = content::RESOURCE_TYPE_SCRIPT,
+  IMAGE = content::RESOURCE_TYPE_IMAGE,
+  FONT_RESOURCE = content::RESOURCE_TYPE_FONT_RESOURCE,
+  SUB_RESOURCE = content::RESOURCE_TYPE_SUB_RESOURCE,
+  OBJECT = content::RESOURCE_TYPE_OBJECT,
+  MEDIA = content::RESOURCE_TYPE_MEDIA,
+  WORKER = content::RESOURCE_TYPE_WORKER,
+  SHARED_WORKER = content::RESOURCE_TYPE_SHARED_WORKER,
+  PREFETCH = content::RESOURCE_TYPE_PREFETCH,
+  FAVICON = content::RESOURCE_TYPE_FAVICON,
+  XHR = content::RESOURCE_TYPE_XHR,
+  PING = content::RESOURCE_TYPE_PING,
+  SERVICE_WORKER = content::RESOURCE_TYPE_SERVICE_WORKER,
+  CSP_REPORT = content::RESOURCE_TYPE_CSP_REPORT,
+  PLUGIN_RESOURCE = content::RESOURCE_TYPE_PLUGIN_RESOURCE,
+
+  // Types of requests not in content::ResourceType.
+  WEB_SOCKET,
+
+  OTHER,

[Devlin, 2017/02/16 16:08:26]

(see other comment, but I wonder if we should put an INVALID here)

[tyoshino (SeeGerritForStatus), 2017/02/16 17:07:37]

Oh. Using OTHER here would make kResourceTypeValues[] look more consistent with
kResourceTypeStrings[] as Devlin suggested, but it's a bit weird that
SUB_RESOURCE, PREFETCH and CSP_REPORT listed here will be converted by
ResourceTypeToString() into "other" which corresponds to OTHER also listed here.

Hmm, on the other hand, e.g.
ExtensionWebRequestEventRouter::GetMatchingListenersImpl() looks up the result
of ToWebRequestResourceType() from RequestFilter::types but it's set by
ParseResourceType() which never pushes any of these 3 types into the types
argument. So, these 3 types are handled not as OTHER stuffs.

Maybe this inconsistency should be cleaned up if not intentional.

[pkalinnikov, 2017/02/16 19:27:33]

I addressed the inconsistency. Please see the global comment.

+};
+
+static_assert(content::RESOURCE_TYPE_LAST_TYPE ==
+                  content::RESOURCE_TYPE_PLUGIN_RESOURCE + 1,
+              "content::ResourceType has been modified.");
+
+inline WebRequestResourceType ToWebRequestResourceType(
+    content::ResourceType type) {
+  return type == content::RESOURCE_TYPE_LAST_TYPE
+             ? WebRequestResourceType::OTHER
+             : static_cast<WebRequestResourceType>(type);
+}
+
+WebRequestResourceType ToWebRequestResourceType(const net::URLRequest* request);

[pkalinnikov, 2017/02/16 15:55:38]

Actually, GetWebRequestResourceType fits this function better, because it's not
a conversion unlike in the above function. WDYT?

[Devlin, 2017/02/16 16:08:26]

I was going to suggest something like WebRequestResourceTypeForRequest or
something, but GetWebRequestResourceType is also good (I'd be fine with either).
 I agree that To* doesn't fit quite as well.

+
+}  // namespace extensions
+
+#endif  // EXTENSIONS_BROWSER_API_WEB_REQUEST_WEB_REQUEST_RESOURCE_TYPE_H_