Introduce WebRequestEventRouterDelegate.

chrome/browser/extensions/api/web_request/web_request_api_helpers.h

Index: chrome/browser/extensions/api/web_request/web_request_api_helpers.h
diff --git a/chrome/browser/extensions/api/web_request/web_request_api_helpers.h b/chrome/browser/extensions/api/web_request/web_request_api_helpers.h
index b5a25771f6e01d66fef932e4a931b0f516838de0..836e0e8f0199f0ec1e3ef970a08ee19ad2289906 100644
--- a/chrome/browser/extensions/api/web_request/web_request_api_helpers.h
+++ b/chrome/browser/extensions/api/web_request/web_request_api_helpers.h
@@ -37,6 +37,8 @@ class URLRequest;
 
 namespace extension_web_request_api_helpers {
 
+#define ARRAYEND(array) (array + arraysize(array))
+
 typedef std::pair<std::string, std::string> ResponseHeader;
 typedef std::vector<ResponseHeader> ResponseHeaders;
 
@@ -312,6 +314,11 @@ void NotifyWebRequestAPIUsed(
     void* browser_context_id,
     scoped_refptr<const extensions::Extension> extension);
 
+// Converts the |name|, |value| pair of a http header to a HttpHeaders
+// dictionary. Ownership is passed to the caller.
+base::DictionaryValue* ToHeaderDictionary(
+    const std::string& name, const std::string& value);
+
 }  // namespace extension_web_request_api_helpers
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_WEB_REQUEST_WEB_REQUEST_API_HELPERS_H_