[builtins] Fix Object.create(null) special case

src/code-stub-assembler.h

Index: src/code-stub-assembler.h
diff --git a/src/code-stub-assembler.h b/src/code-stub-assembler.h
index e391278b8cfd4ed051a844f4a0b97b43bcf7b67c..86bd6dcf16df9ee01336f2faa7fb71b4108f0435 100644
--- a/src/code-stub-assembler.h
+++ b/src/code-stub-assembler.h
@@ -707,7 +707,12 @@ class V8_EXPORT_PRIVATE CodeStubAssembler : public compiler::CodeAssembler {
   // Returns true if any of the |T|'s bits in given |word32| are set.
   template <typename T>
   compiler::Node* IsSetWord32(compiler::Node* word32) {
-    return Word32NotEqual(Word32And(word32, Int32Constant(T::kMask)),
+    return IsSetWord32(word32, T::kMask);
+  }
+
+  // Returns true if any of the |T|'s bits in given |word32| are set.

[Jakob Kummerow, 2016/10/25 19:51:37]

nit: s/|T|/mask/

+  compiler::Node* IsSetWord32(compiler::Node* word32, uint32_t mask) {
+    return Word32NotEqual(Word32And(word32, Int32Constant(mask)),
                           Int32Constant(0));
   }