Fix history importing by delaying DownloadManager creation.

content/browser/download/download_id.cc

Index: content/browser/download/download_id.cc
diff --git a/content/browser/download/download_id.cc b/content/browser/download/download_id.cc
index bef4964b39d22b2114e17a51480a4f9a22759120..8cd7b0ec5a25dc2774e149a5028259b0b817f4c6 100644
--- a/content/browser/download/download_id.cc
+++ b/content/browser/download/download_id.cc
@@ -2,8 +2,15 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include <string>
+
+#include "base/stringprintf.h"
 #include "content/browser/download/download_id.h"
 
+std::string DownloadId::DebugString() const {
+  return base::StringPrintf("%p:%d", domain_, local_id_);
+}
+
 std::ostream& operator<<(std::ostream& out, const DownloadId& global_id) {
-  return out << global_id.manager_ << ":" << global_id.local();
+  return out << global_id.DebugString();
 }