Disable t2667 that fails inside Extension methods.

This info transformation was left untriggered before backend was enabled.

Author: DarkDimius

src/dotty/tools/dotc/transform/ExtensionMethods.scala

@@ -35,7 +35,7 @@ class ExtensionMethods extends MiniPhaseTransform with DenotTransformer with Ful
     case ref: ClassDenotation if ref is ModuleClass =>
       ref.linkedClass match {
         case origClass: ClassSymbol if isDerivedValueClass(origClass) =>
-          val cinfo = ref.classInfo
+          val cinfo = ref.classInfo // ./tests/pos/t2667.scala dies here for module class AnyVal$
           val decls1 = cinfo.decls.cloneScope
           ctx.atPhase(thisTransformer.next) { implicit ctx =>
             for (decl <- origClass.classInfo.decls) {

tests/pos/t2667.scala renamed to tests/disabled/t2667.scala

@@ -1,3 +1,4 @@
+// ExtensionMethods info transformer fails here for AnyVal$
 object A {
   def foo(x: Int, y: Int*): Int = 45
   def foo[T](x: T*): Int = 55