Fix #1868 - Fix logic bug in match

Author: odersky

compiler/src/dotty/tools/dotc/typer/Typer.scala

@@ -1150,7 +1150,7 @@ class Typer extends Namer with TypeAssigner with Applications with Implicits wit
           // classes defined in a such arguments should not be entered into the
           // enclosing class.
           c.exprContext(mdef, exprOwner)
-        case None => c
+        case _ => c
       }
     }
     // necessary in order to mark the typed ahead annotations as definitely typed:

tests/pos/i1868.scala

@@ -0,0 +1,7 @@
+class Test[X](x: X) {
+  def checkSpecialization[Y](y: Y): X = {
+    def specMe[@specialized T]() = ()
+    x
+  }
+  private def checkNameStartsWith(prefix: String) = { (new Exception) }
+}