Simplify refchecks now that it succeeds patmat

Author: retronym

src/compiler/scala/tools/nsc/typechecker/RefChecks.scala

@@ -1822,26 +1822,6 @@ abstract class RefChecks extends Transform {
               transform(pat)
             }
             treeCopy.CaseDef(tree, pat1, transform(guard), transform(body))
-          case LabelDef(_, _, _) if treeInfo.hasSynthCaseSymbol(result) =>
-            savingInPattern {
-              inPattern = true
-              deriveLabelDef(result)(transform)
-            }
-          case Apply(fun, args) if fun.symbol.isLabel && treeInfo.isSynthCaseSymbol(fun.symbol) =>
-            savingInPattern {
-              // scala/bug#7756 If we were in a translated pattern, we can now switch out of pattern mode, as the label apply signals
-              //         that we are in the user-supplied code in the case body.
-              //
-              //         Relies on the translation of:
-              //            (null: Any) match { case x: List[_] => x; x.reverse; case _ => }'
-              //         to:
-              //            <synthetic> val x2: List[_] = (x1.asInstanceOf[List[_]]: List[_]);
-              //                  matchEnd4({ x2; x2.reverse}) // case body is an argument to a label apply.
-              inPattern = false
-              super.transform(result)
-            }
-          case ValDef(_, _, _, _) if treeInfo.hasSynthCaseSymbol(result) =>
-            deriveValDef(result)(transform) // scala/bug#7716 Don't refcheck the tpt of the synthetic val that holds the selector.
           case _ =>
             result.transform(this)
         }