[turbofan] Unify function prototype constant folding.

test/unittests/compiler/js-typed-lowering-unittest.cc

Index: test/unittests/compiler/js-typed-lowering-unittest.cc
diff --git a/test/unittests/compiler/js-typed-lowering-unittest.cc b/test/unittests/compiler/js-typed-lowering-unittest.cc
index 74f943b4fa22da500b9516c5cd643434bffec675..904d5f7406d028dac6e9a186c17c0b98b0061656 100644
--- a/test/unittests/compiler/js-typed-lowering-unittest.cc
+++ b/test/unittests/compiler/js-typed-lowering-unittest.cc
@@ -814,24 +814,6 @@ TEST_F(JSTypedLoweringTest, JSLoadNamedStringLength) {
 }
 
 
-TEST_F(JSTypedLoweringTest, JSLoadNamedFunctionPrototype) {
-  VectorSlotPair feedback;
-  Handle<Name> name = factory()->prototype_string();
-  Handle<JSFunction> function = isolate()->object_function();
-  Handle<JSObject> function_prototype(JSObject::cast(function->prototype()));
-  Node* const receiver = Parameter(Type::Constant(function, zone()), 0);
-  Node* const vector = Parameter(Type::Internal(), 1);
-  Node* const context = Parameter(Type::Internal(), 2);
-  Node* const effect = graph()->start();
-  Node* const control = graph()->start();
-  Reduction const r = Reduce(graph()->NewNode(
-      javascript()->LoadNamed(name, feedback), receiver, vector, context,
-      EmptyFrameState(), EmptyFrameState(), effect, control));
-  ASSERT_TRUE(r.Changed());
-  EXPECT_THAT(r.replacement(), IsHeapConstant(function_prototype));
-}
-
-
 // -----------------------------------------------------------------------------
 // JSAdd