[turbofan] Optimize loads of global constants in JSTypedLowering.

src/types.cc

Index: src/types.cc
diff --git a/src/types.cc b/src/types.cc
index 6724b7c2626abe0c6173d3b0817302dd217b38ce..e9a9acb66e8850c5b3a7a1d40b2b299807e0ef33 100644
--- a/src/types.cc
+++ b/src/types.cc
@@ -277,6 +277,7 @@ TypeImpl<Config>::BitsetType::Lub(i::Map* map) {
     case FOREIGN_TYPE:
     case SCRIPT_TYPE:
     case CODE_TYPE:
+    case PROPERTY_CELL_TYPE:
       return kInternal & kTaggedPointer;
     default:
       UNREACHABLE();