Lint/AssignmentInCondition not triggered for property access

[ptarjan]

Expected behavior

if foo.bar = baz
  91
end

Should trigger the Lint/AssignmentInCondition

Actual behavior

No error

Steps to reproduce the problem

$ cat a.rb
if foo.bar = baz
  91
end
$ rubocop a.rb
Inspecting 1 file
.

1 file inspected, no offenses detected

RuboCop version

$ rubocop -V
0.38.0 (using Parser 2.3.0.6, running on ruby 2.1.2 x86_64-darwin15.0)

[alexdowad]

I've got a fix.