add checks needed for covariant generics, and List<E>

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$(E) {
       ListIterable() {
         super.IterableBase();
       }
       get [core.$iterator]() {
@@ skipping 55 matching lines @@
         for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           if (test(this[core.$elementAt](i)))
             return true;
           if (length != this[core.$length]) {
             throw new core.ConcurrentModificationError(this);
           }
         }
         return false;
       }
       [core.$firstWhere](test, opts) {
+        dart.as(test, dart.functionType(core.bool, [E]));
         let orElse = opts && 'orElse' in opts ? opts.orElse : null;
+        dart.as(orElse, dart.functionType(E, []));
         let length = this[core.$length];
         for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           let element = this[core.$elementAt](i);
           if (test(element))
             return element;
           if (length != this[core.$length]) {
             throw new core.ConcurrentModificationError(this);
           }
         }
         if (orElse != null)
           return orElse();
         throw IterableElementError.noElement();
       }
       [core.$lastWhere](test, opts) {
+        dart.as(test, dart.functionType(core.bool, [E]));
         let orElse = opts && 'orElse' in opts ? opts.orElse : null;
+        dart.as(orElse, dart.functionType(E, []));
         let length = this[core.$length];
         for (let i = dart.notNull(length) - 1; dart.notNull(i) >= 0; i = dart.notNull(i) - 1) {
           let element = this[core.$elementAt](i);
           if (test(element))
             return element;
           if (length != this[core.$length]) {
             throw new core.ConcurrentModificationError(this);
           }
         }
         if (orElse != null)
@@ skipping 679 matching lines @@
       [core.$contains](element) {
         return false;
       }
       [core.$every](test) {
         return true;
       }
       [core.$any](test) {
         return false;
       }
       [core.$firstWhere](test, opts) {
+        dart.as(test, dart.functionType(core.bool, [E]));
         let orElse = opts && 'orElse' in opts ? opts.orElse : null;
+        dart.as(orElse, dart.functionType(E, []));
         if (orElse != null)
           return orElse();
         throw IterableElementError.noElement();
       }
       [core.$lastWhere](test, opts) {
+        dart.as(test, dart.functionType(core.bool, [E]));
         let orElse = opts && 'orElse' in opts ? opts.orElse : null;
+        dart.as(orElse, dart.functionType(E, []));
         if (orElse != null)
           return orElse();
         throw IterableElementError.noElement();
       }
       [core.$singleWhere](test, opts) {
+        dart.as(test, dart.functionType(core.bool, [E]));
         let orElse = opts && 'orElse' in opts ? opts.orElse : null;
+        dart.as(orElse, dart.functionType(E, []));
         if (orElse != null)
           return orElse();
         throw IterableElementError.noElement();
       }
       [core.$join](separator) {
         if (separator === void 0)
           separator = "";
         return "";
       }
       [core.$where](test) {
@@ skipping 449 matching lines @@
     let __CastType6 = dart.typedef('__CastType6', () => dart.functionType(core.bool, [T]));
     return __CastType6;
   });
   let __CastType6 = __CastType6$();
   let FixedLengthListMixin$ = dart.generic(function(E) {
     class FixedLengthListMixin extends core.Object {
       set length(newLength) {
         throw new core.UnsupportedError("Cannot change the length of a fixed-length list");
       }
       add(value) {
+        dart.as(value, E);
         throw new core.UnsupportedError("Cannot add to a fixed-length list");
       }
       insert(index, value) {
+        dart.as(value, E);
         throw new core.UnsupportedError("Cannot add to a fixed-length list");
       }
       insertAll(at, iterable) {
         throw new core.UnsupportedError("Cannot add to a fixed-length list");
       }
       addAll(iterable) {
         throw new core.UnsupportedError("Cannot add to a fixed-length list");
       }
       remove(element) {
         throw new core.UnsupportedError("Cannot remove from a fixed-length list");
@@ skipping 19 matching lines @@
       replaceRange(start, end, iterable) {
         throw new core.UnsupportedError("Cannot remove from a fixed-length list");
       }
     }
     return FixedLengthListMixin;
   });
   let FixedLengthListMixin = FixedLengthListMixin$();
   let UnmodifiableListMixin$ = dart.generic(function(E) {
     class UnmodifiableListMixin extends core.Object {
       [core.$set](index, value) {
+        dart.as(value, E);
         throw new core.UnsupportedError("Cannot modify an unmodifiable list");
       }
       set [core.$length](newLength) {
         throw new core.UnsupportedError("Cannot change the length of an unmodifiable list");
       }
       [core.$setAll](at, iterable) {
         throw new core.UnsupportedError("Cannot modify an unmodifiable list");
       }
       [core.$add](value) {
+        dart.as(value, E);
         throw new core.UnsupportedError("Cannot add to an unmodifiable list");
       }
       [core.$insert](index, value) {
+        dart.as(value, E);
         throw new core.UnsupportedError("Cannot add to an unmodifiable list");
       }
       [core.$insertAll](at, iterable) {
         throw new core.UnsupportedError("Cannot add to an unmodifiable list");
       }
       [core.$addAll](iterable) {
         throw new core.UnsupportedError("Cannot add to an unmodifiable list");
       }
       [core.$remove](element) {
         throw new core.UnsupportedError("Cannot remove from an unmodifiable list");
       }
       [core.$removeWhere](test) {
         throw new core.UnsupportedError("Cannot remove from an unmodifiable list");
       }
       [core.$retainWhere](test) {
         throw new core.UnsupportedError("Cannot remove from an unmodifiable list");
       }
       [core.$sort](compare) {
         if (compare === void 0)
           compare = null;
+        dart.as(compare, core.Comparator$(E));
         throw new core.UnsupportedError("Cannot modify an unmodifiable list");
       }
       [core.$shuffle](random) {
         if (random === void 0)
           random = null;
         throw new core.UnsupportedError("Cannot modify an unmodifiable list");
       }
       [core.$clear]() {
         throw new core.UnsupportedError("Cannot clear an unmodifiable list");
       }
       [core.$removeAt](index) {
         throw new core.UnsupportedError("Cannot remove from an unmodifiable list");
       }
       [core.$removeLast]() {
         throw new core.UnsupportedError("Cannot remove from an unmodifiable list");
       }
       [core.$setRange](start, end, iterable, skipCount) {
+        dart.as(iterable, core.Iterable$(E));
         if (skipCount === void 0)
           skipCount = 0;
         throw new core.UnsupportedError("Cannot modify an unmodifiable list");
       }
       [core.$removeRange](start, end) {
         throw new core.UnsupportedError("Cannot remove from an unmodifiable list");
       }
       [core.$replaceRange](start, end, iterable) {
         throw new core.UnsupportedError("Cannot remove from an unmodifiable list");
       }
       [core.$fillRange](start, end, fillValue) {
         if (fillValue === void 0)
           fillValue = null;
+        dart.as(fillValue, E);
         throw new core.UnsupportedError("Cannot modify an unmodifiable list");
       }
     }
     UnmodifiableListMixin[dart.implements] = () => [core.List$(E)];
     return UnmodifiableListMixin;
   });
   let UnmodifiableListMixin = UnmodifiableListMixin$();
   let FixedLengthListBase$ = dart.generic(function(E) {
     class FixedLengthListBase extends dart.mixin(collection.ListBase$(E), FixedLengthListMixin$(E)) {}
     return FixedLengthListBase;
@@ skipping 51 matching lines @@
       forEach(f) {
         let length = this[_values][core.$length];
         for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
           f(i, this[_values][core.$get](i));
           if (length != this[_values][core.$length]) {
             throw new core.ConcurrentModificationError(this[_values]);
           }
         }
       }
       set(key, value) {
+        dart.as(value, E);
         throw new core.UnsupportedError("Cannot modify an unmodifiable map");
       }
       putIfAbsent(key, ifAbsent) {
         throw new core.UnsupportedError("Cannot modify an unmodifiable map");
       }
       remove(key) {
         throw new core.UnsupportedError("Cannot modify an unmodifiable map");
       }
       clear() {
         throw new core.UnsupportedError("Cannot modify an unmodifiable map");
@@ skipping 504 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 = {}));