[stubs] Cleanup CSA::BitFieldDecode() and friends.

src/builtins/builtins-sharedarraybuffer.cc

Index: src/builtins/builtins-sharedarraybuffer.cc
diff --git a/src/builtins/builtins-sharedarraybuffer.cc b/src/builtins/builtins-sharedarraybuffer.cc
index 4d7c3a7a88adbfe7455b9056a680230e154d8744..f7d5c38341620f93e7ee7058319822c24f009450 100644
--- a/src/builtins/builtins-sharedarraybuffer.cc
+++ b/src/builtins/builtins-sharedarraybuffer.cc
@@ -52,8 +52,9 @@ void ValidateSharedTypedArray(CodeStubAssembler* a, compiler::Node* tagged,
   // Fail if the array's JSArrayBuffer is not shared.
   a->Bind(&is_typed_array);
   Node* array_buffer = a->LoadObjectField(tagged, JSTypedArray::kBufferOffset);
-  Node* is_buffer_shared = a->BitFieldDecode<JSArrayBuffer::IsShared>(
-      a->LoadObjectField(array_buffer, JSArrayBuffer::kBitFieldSlot));
+  Node* is_buffer_shared =
+      a->IsSetWord32<JSArrayBuffer::IsShared>(a->LoadObjectField(
+          array_buffer, JSArrayBuffer::kBitFieldSlot, MachineType::Uint32()));
   a->Branch(is_buffer_shared, &is_shared, &not_shared);
   a->Bind(&not_shared);
   a->Goto(&invalid);