Reland "[turbofan] Discard the shared code entry in the optimized code map."

src/crankshaft/hydrogen-instructions.h

Index: src/crankshaft/hydrogen-instructions.h
diff --git a/src/crankshaft/hydrogen-instructions.h b/src/crankshaft/hydrogen-instructions.h
index 7bbdfefd7e62c0f84fc6c097b9b2911e7e5eb877..6d1c47bcb86649080229d2a85e6a744ec1a70094 100644
--- a/src/crankshaft/hydrogen-instructions.h
+++ b/src/crankshaft/hydrogen-instructions.h
@@ -5363,11 +5363,6 @@ class HObjectAccess final {
                          SharedFunctionInfo::kOptimizedCodeMapOffset);
   }
 
-  static HObjectAccess ForOptimizedCodeMapSharedCode() {
-    return HObjectAccess(kInobject, FixedArray::OffsetOfElementAt(
-                                        SharedFunctionInfo::kSharedCodeIndex));
-  }
-
   static HObjectAccess ForFunctionContextPointer() {
     return HObjectAccess(kInobject, JSFunction::kContextOffset);
   }