Mark foo[:bar] as not complex in Style/TernaryParentheses cop

[onk]

Square brackets behavior is now same as Style/RedundantParentheses.

# EnforcedStyle: require_parentheses_when_complex
#
# # bad
# foo = (bar[:baz]) ? a : b
#
# # good
# foo = bar[:baz] ? a : b

It seems better to extract non_complex_type? to mixin and
Style/RedundantParentheses and Style/TernaryParentheses
use it even if incompatibility comes.

---

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  and description in grammatically correct, complete sentences.
• Updated cop documentation with rake generate_cops_documentation (required only when you've added a new cop or changed the configuration/documentation of an existing cop).

[bbatsov]

It seems better to extract non_complex_type? to mixin and
Style/RedundantParentheses and Style/TernaryParentheses
use it even if incompatibility comes.

Yeah, guess this would be best.