[turbofan] Base JSCreateClosure comparison on location.

This changes hashing and comparison functions for JSCreateClosure
operators to be based in the handle location instead of the referenced
object identity. This is in sync with all other JS operators.

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/1388233007

Cr-Commit-Position: refs/heads/master@{#31225}

src/compiler/js-operator.cc

@@ -423,7 +423,7 @@ const CreateArgumentsParameters& CreateArgumentsParametersOf(
 bool operator==(CreateClosureParameters const& lhs,
                 CreateClosureParameters const& rhs) {
   return lhs.pretenure() == rhs.pretenure() &&
-         lhs.shared_info().is_identical_to(rhs.shared_info());
+         lhs.shared_info().location() == rhs.shared_info().location();
 }
 
 
@@ -434,9 +434,7 @@ bool operator!=(CreateClosureParameters const& lhs,
 
 
 size_t hash_value(CreateClosureParameters const& p) {
-  // TODO(mstarzinger): Include hash of the SharedFunctionInfo here.
-  base::hash<PretenureFlag> h;
-  return h(p.pretenure());
+  return base::hash_combine(p.pretenure(), p.shared_info().location());
 }