move Mockery#stub_method call to ObjectMethods

Mock wasn't the right place for calling it. The new yield mechanism is
more general and less ugly, and allocates responsibilities more
appropriately.

lib/mocha/mock.rb

@@ -357,11 +357,11 @@ def any_expectations?
     end
 
     # @private
-    def anticipates(method_name_or_hash, backtrace = nil, object = Mock.new(@mockery))
+    def anticipates(method_name_or_hash, backtrace = nil, &block)
       ExpectationSetting.new(Array(method_name_or_hash).map do |*args|
         args = args.flatten
         method_name = args.shift
-        Mockery.instance.stub_method(object, method_name) unless object.is_a?(Mock)
+        yield method_name if block
         ensure_method_not_already_defined(method_name)
         expectation = Expectation.new(self, method_name, backtrace)
         expectation.returns(args.shift) unless args.empty?

lib/mocha/object_methods.rb

@@ -147,7 +147,9 @@ def anticipates(expected_methods_vs_return_values)
       if frozen?
         raise StubbingError.new("can't stub method on frozen object: #{mocha_inspect}", caller)
       end
-      mocha.anticipates(expected_methods_vs_return_values, caller, self)
+      mocha.anticipates(expected_methods_vs_return_values, caller) do |method_name|
+        Mockery.instance.stub_method(self, method_name)
+      end
     end
   end
 end