Bug 1602383: Make InitializeDllBlocklistOOP a no-op on aarch64; r=mhowell

Differential Revision: https://phabricator.services.mozilla.com/D56380

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

browser/app/winlauncher/DllBlocklistInit.cpp

@@ -23,10 +23,11 @@ extern "C" IMAGE_DOS_HEADER __ImageBase;
 
 namespace mozilla {
 
-#if defined(MOZ_ASAN)
+#if defined(MOZ_ASAN) || defined(_M_ARM64)
 
 // This DLL blocking code is incompatible with ASAN because
 // it is able to execute before ASAN itself has even initialized.
+// Also, AArch64 has not been tested with this.
 LauncherVoidResultWithLineInfo InitializeDllBlocklistOOP(
     const wchar_t* aFullImagePath, HANDLE aChildProcess) {
   return mozilla::Ok();
@@ -126,6 +127,6 @@ LauncherVoidResultWithLineInfo InitializeDllBlocklistOOP(
   return Ok();
 }
 
-#endif  // defined(MOZ_ASAN)
+#endif  // defined(MOZ_ASAN) || defined(_M_ARM64)
 
 }  // namespace mozilla

browser/app/winlauncher/LauncherProcessWin.cpp

@@ -43,12 +43,7 @@
 static mozilla::LauncherVoidResult PostCreationSetup(
     const wchar_t* aFullImagePath, HANDLE aChildProcess,
     HANDLE aChildMainThread, const bool aIsSafeMode) {
-  // The AArch64 build has not yet been tested with this.
-#if defined(_M_ARM64)
-  return mozilla::Ok();
-#else
   return mozilla::InitializeDllBlocklistOOP(aFullImagePath, aChildProcess);
-#endif  // defined(_M_ARM64)
 }
 
 #if !defined( \