If_else kernel requires following additional type support 

• Decimal type (trivial as there's fixed sized binary support already)
• Dict type
• Union Type
• Timestamp with time zone
• Lists
• Structs

Reporter: Niranda Perera / @nirandaperera
Assignee: David Li / @lidavidm

Related issues:

• [C++] if_else kernel doesn't accept all types (is duplicated by)
• [C++] Add additional type support for if_else kernel (relates to)
• [C++] Improve type support for 'coalesce' kernel (relates to)
• [C++] Reconcile type promotion rules between if_else, case_when, coalesce, select (is related to)
• [C++] Optimize dictionary support in kernels/Support nulls in DictionaryUnifier (is related to)
• [R] Remove warning about factor conversion to string in if_else() (is depended upon by)
• [R] Include unused factor levels in coalesce() and if_else() output (is depended upon by)

PRs and other links:

• GitHub Pull Request #11218

_{Note: This issue was originally created as ARROW-13358. Please see the migration documentation for further details.}