Document BasicObject does not implement #object_id and #send [ci skip]

Fixes [Bug #10422]

gc.c

@@ -3489,6 +3489,8 @@ rb_memory_id(VALUE obj)
  *  Note: that some objects of builtin classes are reused for optimization.
  *  This is the case for immediate values and frozen string literals.
  *
+ *  BasicObject implements +__id__+, Kernel implements +object_id+.
+ *
  *  Immediate values are not passed by reference but are passed by value:
  *  +nil+, +true+, +false+, Fixnums, Symbols, and some Floats.
  *

vm_eval.c

@@ -951,6 +951,8 @@ send_internal(int argc, const VALUE *argv, VALUE recv, call_type scope)
  *  When the method is identified by a string, the string is converted
  *  to a symbol.
  *
+ *  BasicObject implements +__send__+, Kernel implements +send+.
+ *
  *     class Klass
  *       def hello(*args)
  *         "Hello " + args.join(' ')