Bug 1817313 - Make startupcache/ buildable outside of a unified build environment r=andi

Differential Revision: https://phabricator.services.mozilla.com/D170124

startupcache/StartupCacheInfo.cpp

@@ -3,10 +3,12 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+#include "StartupCache.h"
 #include "StartupCacheInfo.h"
 
 #include "mozilla/Components.h"
 #include "mozilla/RefPtr.h"
+#include "mozilla/StaticPtr.h"
 
 using namespace mozilla;
 using namespace mozilla::scache;

startupcache/moz.build

@@ -32,5 +32,3 @@ XPIDL_SOURCES += [
 ]
 
 FINAL_LIBRARY = "xul"
-
-REQUIRES_UNIFIED_BUILD = True