Fix an issue that we didn't clean url request properly.

content/browser/download/download_item_impl.cc

Index: content/browser/download/download_item_impl.cc
diff --git a/content/browser/download/download_item_impl.cc b/content/browser/download/download_item_impl.cc
index 966bbae3807574f5ff580ccdaecb4a680d5046b7..a46a353b990606cd2bd2888f212249733dab61cf 100644
--- a/content/browser/download/download_item_impl.cc
+++ b/content/browser/download/download_item_impl.cc
@@ -1061,6 +1061,12 @@ void DownloadItemImpl::UpdateValidatorsOnResumption(
   // notified when the download transitions to the IN_PROGRESS state.
 }
 
+void DownloadItemImpl::CancelRequestWithOffset(int64_t offset) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  if (job_)
+    job_->CancelRequestWithOffset(offset);
+}
+
 void DownloadItemImpl::NotifyRemoved() {
   for (auto& observer : observers_)
     observer.OnDownloadRemoved(this);
@@ -1303,6 +1309,8 @@ void DownloadItemImpl::StartDownload() {
                  base::Unretained(download_file_.get()),
                  base::Bind(&DownloadItemImpl::OnDownloadFileInitialized,
                             weak_ptr_factory_.GetWeakPtr()),
+                 base::Bind(&DownloadItemImpl::CancelRequestWithOffset,
+                            weak_ptr_factory_.GetWeakPtr()),
                  received_slices_));
 }