[NFC] Add HeapType::isMaybeShared(BasicHeapType) utility (#6773)

This abbreviates a common pattern where we first had to check whether a
heap type was basic, then if it was, get its unshared version and
compare it to some expected BasicHeapType.

Suggested in

https://github.com/WebAssembly/binaryen/pull/6771#discussion_r1683005495.

1 files changed, 1 insertions, 2 deletions

diff --git a/src/tools/fuzzing/heap-types.cpp b/src/tools/fuzzing/heap-types.cpp
index c1c13bc0a..7eaf23701 100644
--- a/src/tools/fuzzing/heap-types.cpp
+++ b/src/tools/fuzzing/heap-types.cpp
@@ -759,8 +759,7 @@ void Inhabitator::markExternRefsNullable() {
     auto children = type.getTypeChildren();
     for (size_t i = 0; i < children.size(); ++i) {
       auto child = children[i];
-      if (child.isRef() && child.getHeapType().isBasic() &&
-          child.getHeapType().getBasic(Unshared) == HeapType::ext &&
+      if (child.isRef() && child.getHeapType().isMaybeShared(HeapType::ext) &&
           child.isNonNullable()) {
         markNullable({type, i});
       }