Bug 1824465 - Part 1: Introduce ReleaseAssertIsOnMainThread, r=xpcom-reviewers,emilio,kmag

This is like AssertIsOnMainThread, except with a release assert.

Differential Revision: https://phabricator.services.mozilla.com/D173716

xpcom/threads/MainThreadUtils.h

@@ -7,6 +7,7 @@
 #ifndef MainThreadUtils_h_
 #define MainThreadUtils_h_
 
+#include "mozilla/Assertions.h"
 #include "mozilla/ThreadSafety.h"
 #include "nscore.h"
 
@@ -47,6 +48,11 @@ inline void AssertIsOnMainThread()
     MOZ_ASSERT_CAPABILITY(sMainThreadCapability) {}
 #  endif
 
+inline void ReleaseAssertIsOnMainThread()
+    MOZ_ASSERT_CAPABILITY(sMainThreadCapability) {
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+}
+
 }  // namespace mozilla
 
 #endif