[Downloads] Always call DM::StartDownload() for explicit downloads.

chrome/browser/extensions/webstore_installer.cc

Index: chrome/browser/extensions/webstore_installer.cc
diff --git a/chrome/browser/extensions/webstore_installer.cc b/chrome/browser/extensions/webstore_installer.cc
index a97ec7699e4d9ec41657ab29a8fa2220e046f9c1..fa910f3ee4c998cec017007219b4544b67fb6b86 100644
--- a/chrome/browser/extensions/webstore_installer.cc
+++ b/chrome/browser/extensions/webstore_installer.cc
@@ -459,8 +459,9 @@ void WebstoreInstaller::OnDownloadStarted(
     const std::string& extension_id,
     DownloadItem* item,
     content::DownloadInterruptReason interrupt_reason) {
-  if (!item) {
-    DCHECK_NE(content::DOWNLOAD_INTERRUPT_REASON_NONE, interrupt_reason);
+  if (!item || interrupt_reason != content::DOWNLOAD_INTERRUPT_REASON_NONE) {
+    if (item)
+      item->Remove();
     ReportFailure(content::DownloadInterruptReasonToString(interrupt_reason),
                   FAILURE_REASON_OTHER);
     return;