Pump the http version to download system.

content/browser/download/parallel_download_utils.cc

Index: content/browser/download/parallel_download_utils.cc
diff --git a/content/browser/download/parallel_download_utils.cc b/content/browser/download/parallel_download_utils.cc
index 4327d8d909a4fa76802fcd63c7ecb543320a04fa..b3e6ee8a5f309f9a8633644784e0f9551bb49f97 100644
--- a/content/browser/download/parallel_download_utils.cc
+++ b/content/browser/download/parallel_download_utils.cc
@@ -43,10 +43,11 @@ bool compareReceivedSlices(const DownloadItem::ReceivedSlice& lhs,
 }  // namespace
 
 bool ShouldUseParallelDownload(const DownloadCreateInfo& create_info) {
+  // To enable parallel download, following conditions need to be satisfied.
   // 1. Accept-Ranges, Content-Length and strong validators response headers.
   // 2. Feature |kParallelDownloading| enabled.
   // 3. Content-Length is no less than the minimum slice size configuration.
-  // 3. TODO(xingliu) HTTP/1.1 protocol, not QUIC or HTTP/2.
+  // 3. HTTP/1.1 protocol, not QUIC nor HTTP/1.0.
 
   // Etag and last modified are stored into DownloadCreateInfo in
   // DownloadRequestCore only if the response header complies to the strong
@@ -56,6 +57,8 @@ bool ShouldUseParallelDownload(const DownloadCreateInfo& create_info) {
 
   return has_strong_validator && create_info.accept_range &&
          create_info.total_bytes >= GetMinSliceSizeConfig() &&
+         create_info.connection_info ==
+             net::HttpResponseInfo::CONNECTION_INFO_HTTP1_1 &&
          base::FeatureList::IsEnabled(features::kParallelDownloading);
 }