Fix inline-named-typeargs.scala by handling named type parameter patterns

Author: OlivierBlanvillain

compiler/src/dotty/tools/dotc/ast/TreeInfo.scala

@@ -517,8 +517,8 @@ trait TypedTreeInfo extends TreeInfo[Type] { self: Trees.Instance[Type] =>
       val (meth, targs, argss) = decomposeCall(fn)
       (meth, targs, argss :+ args)
     case TypeApply(fn, targs) =>
-      val (meth, Nil, Nil) = decomposeCall(fn)
-      (meth, targs, Nil)
+      val (meth, targss, args) = decomposeCall(fn)
+      (meth, targs ++ targss, args)
     case _ =>
       (tree, Nil, Nil)
   }

tests/pos/inline-named-typeargs.scala

@@ -0,0 +1,5 @@
+object t1 {
+  inline def construct[Elem, Coll[_]](xs: List[Elem]): Coll[Elem] = ???
+
+  val xs3 = construct[Coll = List](List(1, 2, 3))
+}