Hydrogenized KeyedLoadGeneric stub: Fix string hash retrieval

R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/363293002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22184 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/code-stubs-hydrogen.cc

@@ -1632,6 +1632,8 @@ HValue* CodeStubGraphBuilder<KeyedLoadGenericElementStub>::BuildCodeStub() {
           Add<HLoadNamedField>(key, static_cast<HValue*>(NULL),
           HObjectAccess::ForNameHashField());
 
+      hash = AddUncasted<HShr>(hash, Add<HConstant>(Name::kHashShift));
+
       HValue* value = BuildUncheckedDictionaryElementLoad(receiver,
                                                           properties,
                                                           key,