Remove unecessary code

Author: nicolasstucki

compiler/src/dotty/tools/dotc/core/TypeOps.scala

@@ -15,8 +15,6 @@ import util.{SimpleMap, Property}
 import collection.mutable
 import ast.tpd._
 
-import scala.annotation.tailrec
-
 trait TypeOps { this: Context => // TODO: Make standalone object.
 
   /** The type `tp` as seen from prefix `pre` and owner `cls`. See the spec
@@ -257,8 +255,7 @@ trait TypeOps { this: Context => // TODO: Make standalone object.
                   else tp.baseTypeWithArgs(cls)
                 base.mapReduceOr(identity)(mergeRefined)
               }
-              if (doms.isEmpty) new ErrorType("no parents in common") // This can happen in the union of Any with PhantomAny
-              else doms.map(baseTp).reduceLeft(AndType.apply)
+              doms.map(baseTp).reduceLeft(AndType.apply)
           }
       }
     }