Fix #6214: Set correct owner for splices in quote patterns

[odersky]

No description provided.

[odersky]

@nicolasstucki i6214.scala points out a difference between owners of splices in expressions and patterns:

  def res(x: quoted.Expr[Int]) given tasty.Reflection: quoted.Expr[Int] = x match {
    case '{ val a: Int = $y; 1} => y                     // owner of `y` is `res`
    case _ => '{ val b: Int = ${val c = 2; c.toExpr}; 1} // owner of `c` is `b`, but that seems to be OK
  }

Just wanted top check with you that that's as intended.

[nicolasstucki]

I would also add a test case with nested quoted patterns suc as in

object Test {
  def res(x: quoted.Expr[Int]) given tasty.Reflection: quoted.Expr[Int] = x match {
    case '{ val a: Int = ${ Foo('{ val b: Int = $y }) }; 1} => y
  }
 object Foo {
   def unapply(x: Expr[Int]): Option[Expr[Int]] = Some(x)
 }
}

[nicolasstucki]

That is ok. The owner is later changed during the ReifyQuotes.

[nicolasstucki]

LGTM

I also added another test