Add `type_literal_in_constant_pattern`

[johnpryan]

I recently ran into dart-lang/language#2911 and this seems like a good candidate to add to the recommended set. It's probably something users want more often than not.

[lrhn]

I'd really want this warning to be enabled by default in the analyzer, if at all possible.
Even if it's just as a "hint".

Otherwise, I'd put it in core. It's warning about a highly error-prone pattern, and I'd prefer knowing that packages I depend on are aware of the pitfall, and have taken steps to avoid it.

[devoncarew]

This is approved for the core set.

[Fernandomr88]

so I have a function that basically is this

get<T>() {
 switch(T) {
  case Person:
   //code
  case Dog:
   //code
  }
}

which is called like get<Person>();

and by using the notation suggested by this rule (Person _), it stopped working.

How am I supposed to change my code to be adequate to this linter rule?

[bwilkerson]

It sounds like the rule might need to be changed to not produce a diagnostic if the value being switched over is Type.