fix temp used in postfix ops

lib/runtime/dart/_internal.js

 var _internal;
 (function(exports) {
   'use strict';
   class EfficientLength extends core.Object {
   }
   let ListIterable$ = dart.generic(function(E) {
     class ListIterable extends collection.IterableBase$(E) {
       ListIterable() {
         super.IterableBase();
       }
@@ skipping 1138 matching lines @@
       }
       static insertAllList(list, index, iterable) {
         core.RangeError.checkValueInInterval(index, 0, list.length, "index");
         if (!dart.is(iterable, EfficientLength)) {
           iterable = iterable.toList({growable: false});
         }
         let insertionLength = iterable.length;
         list.length = insertionLength;
         list.setRange(dart.notNull(index) + dart.notNull(insertionLength), list.length, list, index);
         for (let element of iterable) {
-          list.set(((x) => index = dart.notNull(x$) + 1, x$)(index), element);
+          list.set(((x) => index = dart.notNull(x) + 1, x)(index), element);
         }
       }
       static setAllList(list, index, iterable) {
         core.RangeError.checkValueInInterval(index, 0, list.length, "index");
         for (let element of iterable) {
-          list.set(((x) => index = dart.notNull(x$) + 1, x$)(index), element);
+          list.set(((x) => index = dart.notNull(x) + 1, x)(index), element);
         }
       }
       asMapList(l) {
         return new ListMapView(dart.as(l, core.List$(T)));
       }
       static setContainsAll(set, other) {
         for (let element of other) {
           if (!dart.notNull(set.contains(element)))
             return false;
         }
@@ skipping 477 matching lines @@
             }
             less = dart.notNull(less) + 1;
           } else {
             while (true) {
               comp = dart.dinvokef(compare, a.get(great), pivot);
               if (dart.notNull(comp) > 0) {
                 great = dart.notNull(great) - 1;
                 continue;
               } else if (dart.notNull(comp) < 0) {
                 a.set(k, a.get(less));
-                a.set(((x) => less = dart.notNull(x$) + 1, x$)(less), a.get(great));
-                a.set(((x) => great = dart.notNull(x$) - 1, x$)(great), ak);
+                a.set(((x) => less = dart.notNull(x) + 1, x)(less), a.get(great));
+                a.set(((x) => great = dart.notNull(x) - 1, x)(great), ak);
                 break;
               } else {
                 a.set(k, a.get(great));
-                a.set(((x) => great = dart.notNull(x$) - 1, x$)(great), ak);
+                a.set(((x) => great = dart.notNull(x) - 1, x)(great), ak);
                 break;
               }
             }
           }
         }
       } else {
         for (let k = less; dart.notNull(k) <= dart.notNull(great); k = dart.notNull(k) + 1) {
           let ak = a.get(k);
           let comp_pivot1 = dart.dinvokef(compare, ak, pivot1);
           if (dart.notNull(comp_pivot1) < 0) {
             if (k !== less) {
               a.set(k, a.get(less));
               a.set(less, ak);
             }
             less = dart.notNull(less) + 1;
           } else {
             let comp_pivot2 = dart.dinvokef(compare, ak, pivot2);
             if (dart.notNull(comp_pivot2) > 0) {
               while (true) {
                 let comp = dart.dinvokef(compare, a.get(great), pivot2);
                 if (dart.notNull(comp) > 0) {
                   great = dart.notNull(great) - 1;
                   if (dart.notNull(great) < dart.notNull(k))
                     break;
                   continue;
                 } else {
                   comp = dart.dinvokef(compare, a.get(great), pivot1);
                   if (dart.notNull(comp) < 0) {
                     a.set(k, a.get(less));
-                    a.set(((x) => less = dart.notNull(x$) + 1, x$)(less), a.get(great));
-                    a.set(((x) => great = dart.notNull(x$) - 1, x$)(great), ak);
+                    a.set(((x) => less = dart.notNull(x) + 1, x)(less), a.get(great));
+                    a.set(((x) => great = dart.notNull(x) - 1, x)(great), ak);
                   } else {
                     a.set(k, a.get(great));
-                    a.set(((x) => great = dart.notNull(x$) - 1, x$)(great), ak);
+                    a.set(((x) => great = dart.notNull(x) - 1, x)(great), ak);
                   }
                   break;
                 }
               }
             }
           }
         }
       }
       a.set(left, a.get(dart.notNull(less) - 1));
       a.set(dart.notNull(less) - 1, pivot1);
@@ skipping 27 matching lines @@
                 let comp = dart.dinvokef(compare, a.get(great), pivot2);
                 if (comp === 0) {
                   great = dart.notNull(great) - 1;
                   if (dart.notNull(great) < dart.notNull(k))
                     break;
                   continue;
                 } else {
                   comp = dart.dinvokef(compare, a.get(great), pivot1);
                   if (dart.notNull(comp) < 0) {
                     a.set(k, a.get(less));
-                    a.set(((x) => less = dart.notNull(x$) + 1, x$)(less), a.get(great));
-                    a.set(((x) => great = dart.notNull(x$) - 1, x$)(great), ak);
+                    a.set(((x) => less = dart.notNull(x) + 1, x)(less), a.get(great));
+                    a.set(((x) => great = dart.notNull(x) - 1, x)(great), ak);
                   } else {
                     a.set(k, a.get(great));
-                    a.set(((x) => great = dart.notNull(x$) - 1, x$)(great), ak);
+                    a.set(((x) => great = dart.notNull(x) - 1, x)(great), ak);
                   }
                   break;
                 }
               }
             }
           }
         }
         _doSort(a, less, great, compare);
       } else {
         _doSort(a, less, great, compare);
@@ skipping 119 matching lines @@
   exports.ReversedListIterable$ = ReversedListIterable$;
   exports.UnmodifiableListError = UnmodifiableListError;
   exports.NonGrowableListError = NonGrowableListError;
   exports.makeListFixedLength = makeListFixedLength;
   exports.Lists = Lists;
   exports.printToConsole = printToConsole;
   exports.Sort = Sort;
   exports.Symbol = Symbol;
   exports.POWERS_OF_TEN = POWERS_OF_TEN;
 })(_internal || (_internal = {}));