Move MimeTypeResourceHandler before ThrottlingResourceHandler

content/browser/loader/resource_dispatcher_host_impl.cc

 // Copyright (c) 2012 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.
 
 // See http://dev.chromium.org/developers/design-documents/multi-process-resource-loading
 
 #include "content/browser/loader/resource_dispatcher_host_impl.h"
 
 #include <stddef.h>
 
@@ skipping 1702 matching lines @@
     std::unique_ptr<ResourceHandler> handler) {
   // PlzNavigate: do not add ResourceThrottles for main resource requests from
   // the renderer.  Decisions about the navigation should have been done in the
   // initial request.
   if (IsBrowserSideNavigationEnabled() && IsResourceTypeFrame(resource_type) &&
       child_id != -1) {
     DCHECK(request->url().SchemeIs(url::kBlobScheme));
     return handler;
   }
 
-  PluginService* plugin_service = nullptr;
-#if defined(ENABLE_PLUGINS)
-  plugin_service = PluginService::GetInstance();
-#endif
-  // Insert a buffered event handler before the actual one.
-  handler.reset(new MimeTypeResourceHandler(std::move(handler), this,
-                                            plugin_service, request));
-
   ScopedVector<ResourceThrottle> throttles;
 
   // Add a NavigationResourceThrottle for navigations.
   // PlzNavigate: the throttle is unnecessary as communication with the UI
   // thread is handled by the NavigationURLloader.
   if (!IsBrowserSideNavigationEnabled() && IsResourceTypeFrame(resource_type))
     throttles.push_back(new NavigationResourceThrottle(request, delegate()));
 
   if (delegate_) {
     delegate_->RequestBeginning(request,
@@ skipping 10 matching lines @@
   }
 
   // TODO(ricea): Stop looking this up so much.
   ResourceRequestInfoImpl* info = ResourceRequestInfoImpl::ForRequest(request);
   throttles.push_back(scheduler_->ScheduleRequest(child_id, route_id,
                                                   info->IsAsync(), request));
 
   handler.reset(new ThrottlingResourceHandler(std::move(handler), request,
                                               std::move(throttles)));
 
+  PluginService* plugin_service = nullptr;
+#if defined(ENABLE_PLUGINS)
+  plugin_service = PluginService::GetInstance();
+#endif
+
+  // Insert a buffered event handler to sniff the mime type first.
+  handler.reset(new MimeTypeResourceHandler(std::move(handler), this,
+                                            plugin_service, request));
+
   return handler;
 }
 
 void ResourceDispatcherHostImpl::OnReleaseDownloadedFile(int request_id) {
   UnregisterDownloadedTempFile(filter_->child_id(), request_id);
 }
 
 void ResourceDispatcherHostImpl::OnDidChangePriority(
     int request_id,
     net::RequestPriority new_priority,
@@ skipping 919 matching lines @@
   ssl.cert_id = GetCertStore()->StoreCert(ssl_info.cert.get(), child_id);
   response->head.security_info = SerializeSecurityInfo(ssl);
 }
 
 CertStore* ResourceDispatcherHostImpl::GetCertStore() {
   return cert_store_for_testing_ ? cert_store_for_testing_
                                  : CertStore::GetInstance();
 }
 
 }  // namespace content