Bug 1843020 - Re-enable Win32k Lockdown for Utility WMF r=bobowen

Differential Revision: https://phabricator.services.mozilla.com/D183861

ipc/glue/UtilityAudioDecoderParent.cpp

@@ -81,10 +81,8 @@ void UtilityAudioDecoderParent::WMFPreloadForSandbox() {
 #if defined(MOZ_SANDBOX) && defined(XP_WIN)
   // mfplat.dll and mf.dll will be preloaded by
   // wmf::MediaFoundationInitializer::HasInitialized()
-#  if defined(DEBUG)
-  // WMF Shutdown on debug build somehow requires this
+  // WMF Shutdown requires this or it will badly crash
   UtilityProcessImpl::LoadLibraryOrCrash(L"ole32.dll");
-#  endif  // defined(DEBUG)
 
   auto rv = wmf::MediaFoundationInitializer::HasInitialized();
   if (!rv) {

security/sandbox/common/test/SandboxTestingChild.cpp

@@ -91,6 +91,7 @@ void SandboxTestingChild::Bind(Endpoint<PSandboxTestingChild>&& aEndpoint) {
     switch (s->mSandbox) {
       case ipc::SandboxingKind::GENERIC_UTILITY:
         RunTestsGenericUtility(this);
+        RunTestsUtilityAudioDecoder(this, s->mSandbox);
         break;
 #ifdef MOZ_APPLEMEDIA
       case ipc::SandboxingKind::UTILITY_AUDIO_DECODING_APPLE_MEDIA:

security/sandbox/common/test/SandboxTestingChildTests.h

@@ -841,7 +841,7 @@ void RunTestsUtilityAudioDecoder(SandboxTestingChild* child,
 #  endif           // XP_MACOSX
 #else              // XP_UNIX
 #  ifdef XP_WIN
-  RunWinTestWin32k(child, false);
+  RunWinTestWin32k(child);
 #  endif  // XP_WIN
   child->ReportNoTests();
 #endif    // XP_UNIX

security/sandbox/win/src/sandboxbroker/sandboxBroker.cpp

@@ -1500,7 +1500,6 @@ struct GenericUtilitySandboxProps : public UtilitySandboxProps {};
 struct UtilityAudioDecodingWmfSandboxProps : public UtilitySandboxProps {
   UtilityAudioDecodingWmfSandboxProps() {
     mDelayedTokenLevel = sandbox::USER_LIMITED;
-    mUseWin32kLockdown = false;
     mDelayedMitigations = sandbox::MITIGATION_STRICT_HANDLE_CHECKS |
                           sandbox::MITIGATION_DLL_SEARCH_ORDER;
 #ifdef MOZ_WMF