Added member data to classes to support download resumption.

content/browser/download/download_resource_handler.cc

Index: content/browser/download/download_resource_handler.cc
diff --git a/content/browser/download/download_resource_handler.cc b/content/browser/download/download_resource_handler.cc
index d703e1472222e4bbf9506ff013164b8c0eef854f..31d3385ac1ca219e8678d8a577cd2c8d93378f24 100644
--- a/content/browser/download/download_resource_handler.cc
+++ b/content/browser/download/download_resource_handler.cc
@@ -53,7 +53,8 @@ DownloadResourceHandler::DownloadResourceHandler(
       save_info_(save_info),
       buffer_(new content::DownloadBuffer),
       rdh_(rdh),
-      is_paused_(false) {
+      is_paused_(false),
+      start_offset_(0) {
   DCHECK(dl_id.IsValid());
   download_stats::RecordDownloadCount(download_stats::UNTHROTTLED_COUNT);
 }
@@ -100,7 +101,7 @@ bool DownloadResourceHandler::OnResponseStarted(int request_id,
   info->url_chain = request_->url_chain();
   info->referrer_url = GURL(request_->referrer());
   info->start_time = base::Time::Now();
-  info->received_bytes = 0;
+  info->received_bytes = start_offset_;
   info->total_bytes = content_length_;
   info->state = DownloadItem::IN_PROGRESS;
   info->download_id = download_id_;
@@ -108,12 +109,21 @@ bool DownloadResourceHandler::OnResponseStarted(int request_id,
   info->content_disposition = content_disposition_;
   info->mime_type = response->response_head.mime_type;
   download_stats::RecordDownloadMimeType(info->mime_type);
+  info->continued_download = (start_offset_ > 0);
 
   DownloadRequestHandle request_handle(rdh_, global_id_.child_id,
                                        render_view_id_, global_id_.request_id);
 
-  // TODO(ahendrickson) -- Get the last modified time and etag, so we can
-  // resume downloading.
+  // Get the last modified time and etag.
+  const net::HttpResponseHeaders* headers = request_->response_headers();
+  if (headers) {
+    std::string last_modified_hdr;
+    std::string etag;
+    if (headers->EnumerateHeader(NULL, "Last-Modified", &last_modified_hdr))
+      info->last_modified = last_modified_hdr;
+    if (headers->EnumerateHeader(NULL, "ETag", &etag))
+      info->etag = etag;
+  }
 
   CallStartedCB(net::OK);