delete file if resume mode is invalid. DCHECK fails in DownloadItemImpl::OnDownloadRenamedToFinalNa…

content/browser/download/download_item_impl.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.
 
 // File method ordering: Methods in this file are in the same order as
 // in download_item_impl.h, with the following exception: The public
 // interface Start is placed in chronological order with the other
 // (private) routines that together define a DownloadItem's state
 // transitions as the download progresses.  See "Download progression
 // cascade" later in this file.
@@ skipping 1406 matching lines @@
   // DownloadResourceHandler::OnResponseStarted.
   DCHECK_NE(DOWNLOAD_INTERRUPT_REASON_NONE, interrupt_reason);
   Interrupt(interrupt_reason);
 }
 
 // **** End of Download progression cascade
 
 // An error occurred somewhere.
 void DownloadItemImpl::Interrupt(DownloadInterruptReason reason) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK_NE(DOWNLOAD_INTERRUPT_REASON_NONE, reason);
 
   // Somewhat counter-intuitively, it is possible for us to receive an
   // interrupt after we've already been interrupted.  The generation of
   // interrupts from the file thread Renames and the generation of
   // interrupts from disk writes go through two different mechanisms (driven
   // by rename requests from UI thread and by write requests from IO thread,
   // respectively), and since we choose not to keep state on the File thread,
   // this is the place where the races collide.  It's also possible for
   // interrupts to race with cancels.
 
   // Whatever happens, the first one to hit the UI thread wins.
   if (state_ != IN_PROGRESS_INTERNAL && state_ != RESUMING_INTERNAL)
     return;
 
   last_reason_ = reason;
 
   ResumeMode resume_mode = GetResumeMode();
 
   if (state_ == IN_PROGRESS_INTERNAL) {
-    // Cancel (delete file) if we're going to restart; no point in leaving
-    // data around we aren't going to use.  Also cancel if resumption isn't
-    // enabled for the same reason.
+    // Cancel (delete file) if:
+    // 1) we're going to restart.
+    // 2) Resumption isn't possible (download was cancelled or blocked due to
+    //    security restrictions).
+    // 3) Resumption isn't enabled.
+    // No point in leaving data around we aren't going to use.
     ReleaseDownloadFile(resume_mode == RESUME_MODE_IMMEDIATE_RESTART ||
                         resume_mode == RESUME_MODE_USER_RESTART ||
+                        resume_mode == RESUME_MODE_INVALID ||
                         !IsDownloadResumptionEnabled());
 
     // Cancel the originating URL request.
     request_handle_->CancelRequest();
   } else {
     DCHECK(!download_file_.get());
   }
 
   // Reset all data saved, as even if we did save all the data we're going
   // to go through another round of downloading when we resume.
@@ skipping 321 matching lines @@
     case RESUME_MODE_USER_CONTINUE:
       return "USER_CONTINUE";
     case RESUME_MODE_USER_RESTART:
       return "USER_RESTART";
   }
   NOTREACHED() << "Unknown resume mode " << mode;
   return "unknown";
 }
 
 }  // namespace content