Hide names of internal classes from the user by mapping them to the documented

runtime/vm/object_store.h

Index: runtime/vm/object_store.h
===================================================================
--- runtime/vm/object_store.h	(revision 9728)
+++ runtime/vm/object_store.h	(working copy)
@@ -37,6 +37,7 @@
     kListInterface,
     kByteArrayInterface,
     kObjectClass,
+    kIntegerImplementationClass,
     kSmiClass,
     kMintClass,
     kBigintClass,
@@ -125,6 +126,12 @@
     int_interface_ = value.raw();
   }
 
+  RawClass* integer_implementation_class() const {
+    return integer_implementation_class_;
+  }
+  void set_integer_implementation_class(const Class& value) {
+    integer_implementation_class_ = value.raw(); }
+
   RawClass* smi_class() const { return smi_class_; }
   void set_smi_class(const Class& value) { smi_class_ = value.raw(); }
   static intptr_t smi_class_offset() {
@@ -523,6 +530,7 @@
   RawType* function_interface_;
   RawType* number_interface_;
   RawType* int_interface_;
+  RawClass* integer_implementation_class_;
   RawClass* smi_class_;
   RawClass* mint_class_;
   RawClass* bigint_class_;