[Downloads] Do not store error responses during resumption.

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 cef57731792e96e8832ee0c0962b58a5d0f75b8b..a60ecce8e7f71586c6ebe2c6665660517fc044de 100644
--- a/content/browser/download/download_item_impl.cc
+++ b/content/browser/download/download_item_impl.cc
@@ -373,6 +373,7 @@ void DownloadItemImpl::Resume() {
     case INTERRUPTED_INTERNAL:
       auto_resume_count_ = 0;  // User input resets the counter.
       ResumeInterruptedDownload();
+      UpdateObservers();

[svaldez, 2016/01/13 17:29:18]

Does this need to go at the bottom of "AutoResumeIfValid"?

[asanka, 2016/01/28 02:24:17]

Nope. AutoResumeIfValid() may or may not resume the download depending on
whether the download can be resumed automatically. Since it's called after the
download is interrupted, the observers should be updated regardless of what
AutoResumeIfValid() does. Since it's a bit out of place for AutoResumeIfValid()
to update observers if it doesn't do anything, we've placed the
UpdateObservers() call after the AutoResumeIfValid() call. That way, when the
observers are updated, they will see that the download is either interrupted or
{in-progress but with a potentially new interrupt reason}.

       return;
 
     case MAX_DOWNLOAD_INTERNAL_STATE:
@@ -893,6 +894,7 @@ DownloadItemImpl::ResumeMode DownloadItemImpl::GetResumeMode() const {
     case DOWNLOAD_INTERRUPT_REASON_NETWORK_SERVER_DOWN:
     case DOWNLOAD_INTERRUPT_REASON_NETWORK_INVALID_REQUEST:
     case DOWNLOAD_INTERRUPT_REASON_SERVER_FAILED:
+    case DOWNLOAD_INTERRUPT_REASON_SERVER_UNREACHABLE:
     case DOWNLOAD_INTERRUPT_REASON_USER_SHUTDOWN:
     case DOWNLOAD_INTERRUPT_REASON_CRASH:
       if (force_restart)
@@ -1418,6 +1420,7 @@ void DownloadItemImpl::OnResumeRequestStarted(
     DCHECK_EQ(static_cast<DownloadItem*>(this), item);
     return;
   }
+
   // Otherwise, the request failed without passing through
   // DownloadResourceHandler::OnResponseStarted.
   DCHECK_NE(DOWNLOAD_INTERRUPT_REASON_NONE, interrupt_reason);