Add flag to specify if explicitly requested download is from web.

chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.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.
 
 #include "chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.h"
 
 #include <string>
 
 #include "base/base64.h"
 #include "base/logging.h"
@@ skipping 185 matching lines @@
                                   resource_type,
                                   throttles);
 }
 
 void ChromeResourceDispatcherHostDelegate::DownloadStarting(
     net::URLRequest* request,
     content::ResourceContext* resource_context,
     int child_id,
     int route_id,
     int request_id,
-    bool is_new_request,
+    bool is_content_initiated,
     ScopedVector<content::ResourceThrottle>* throttles) {
   BrowserThread::PostTask(
       BrowserThread::UI, FROM_HERE,
       base::Bind(&NotifyDownloadInitiatedOnUI, child_id, route_id));
 
-  // If this isn't a new request, we've seen this before and added the safe
-  // browsing resource throttle already so no need to add it again. This code
-  // path is only hit for requests initiated through the browser, and not the
-  // web, so no need to add the download throttle.
-  if (is_new_request) {
+  // If it's from the web, we don't trust it, so we push the throttle on.
+  if (is_content_initiated) {
+    throttles->push_back(new DownloadResourceThrottle(
+        download_request_limiter_, child_id, route_id, request_id,
+        request->method()));
+  }
+
+  // If this isn't a new request, we've seen this before and added the standard
+  //  resource throttles already so no need to add it again.
+  if (!request->is_pending()) {
     AppendStandardResourceThrottles(request,
                                     resource_context,
                                     child_id,
                                     route_id,
                                     ResourceType::MAIN_FRAME,
                                     throttles);
-  } else {
-    throttles->push_back(new DownloadResourceThrottle(
-        download_request_limiter_, child_id, route_id, request_id,
-        request->method()));
   }
 }
 
 bool ChromeResourceDispatcherHostDelegate::AcceptSSLClientCertificateRequest(
     net::URLRequest* request, net::SSLCertRequestInfo* cert_request_info) {
   if (request->load_flags() & net::LOAD_PREFETCH)
     return false;
 
   ChromeURLRequestUserData* user_data = ChromeURLRequestUserData::Get(request);
   if (user_data && user_data->is_prerender()) {
@@ skipping 218 matching lines @@
   if (base::Base64Encode(serialized, &hashed)) {
     // If successful, swap the header value with the new one.
     // Note that the list of IDs and the header could be temporarily out of sync
     // if IDs are added as we are recreating the header, but we're OK with those
     // descrepancies.
     variation_ids_header_ = hashed;
   } else {
     DVLOG(1) << "Failed to base64 encode Variation IDs value: " << serialized;
   }
 }