Bug 1570179: Clear cached directories after sending shutdown notifications. r=froydnj

Differential Revision: https://phabricator.services.mozilla.com/D39983

--HG--
extra : moz-landing-system : lando

toolkit/xre/nsXREDirProvider.cpp

@@ -1073,9 +1073,6 @@ nsXREDirProvider::DoStartup() {
 void nsXREDirProvider::DoShutdown() {
   AUTO_PROFILER_LABEL("nsXREDirProvider::DoShutdown", OTHER);
 
-  gDataDirProfileLocal = nullptr;
-  gDataDirProfile = nullptr;
-
   if (mProfileNotified) {
     nsCOMPtr<nsIObserverService> obsSvc =
         mozilla::services::GetObserverService();
@@ -1104,6 +1101,9 @@ void nsXREDirProvider::DoShutdown() {
     mProfileNotified = false;
   }
 
+  gDataDirProfileLocal = nullptr;
+  gDataDirProfile = nullptr;
+
   if (XRE_IsParentProcess()) {
 #if defined(MOZ_SANDBOX)
     mozilla::Unused << DeleteDirIfExists(mContentProcessSandboxTempDir);