Add a ResourceScheduler to ResourceDispatcherHost.

content/common/resource_messages.h

Index: content/common/resource_messages.h
diff --git a/content/common/resource_messages.h b/content/common/resource_messages.h
index e065419d7f4b2f46e1223fbc593670448aa23f61..abe4964517b7f394e2c69444869429f5c1d64902 100644
--- a/content/common/resource_messages.h
+++ b/content/common/resource_messages.h
@@ -13,6 +13,7 @@
 #include "content/public/common/common_param_traits.h"
 #include "content/public/common/resource_response.h"
 #include "ipc/ipc_message_macros.h"
+#include "net/base/request_priority.h"
 #include "webkit/glue/resource_request_body.h"
 
 #ifndef CONTENT_COMMON_RESOURCE_MESSAGES_H_
@@ -147,7 +148,7 @@ IPC_STRUCT_BEGIN(ResourceHostMsg_Request)
   IPC_STRUCT_MEMBER(ResourceType::Type, resource_type)
 
   // The priority of this request.
-  IPC_STRUCT_MEMBER(WebKit::WebURLRequest::Priority, priority)
+  IPC_STRUCT_MEMBER(net::RequestPriority, priority)
 
   // Used by plugin->browser requests to get the correct net::URLRequestContext.
   IPC_STRUCT_MEMBER(uint32, request_context)
@@ -300,3 +301,8 @@ IPC_MESSAGE_ROUTED1(ResourceHostMsg_UploadProgress_ACK,
 // Sent when the renderer process deletes a resource loader.
 IPC_MESSAGE_CONTROL1(ResourceHostMsg_ReleaseDownloadedFile,
                      int /* request_id */)
+
+// Sent by the renderer when a resource request changes priority.
+IPC_MESSAGE_ROUTED2(ResourceHostMsg_DidChangePriority,
+                    int /* request_id */,
+                    net::RequestPriority)