fix to run against latest analyzer

lib/runtime/dart/collection.js

 dart_library.library('dart/collection', null, /* Imports */[
   'dart/_runtime',
   'dart/core'
 ], /* Lazy imports */[
   'dart/_internal',
   'dart/_js_helper',
   'dart/math'
 ], function(exports, dart, core, _internal, _js_helper, math) {
   'use strict';
   let dartx = dart.dartx;
@@ skipping 487 matching lines @@
             equals = _defaultEquals;
           }
         }
         return new (_CustomHashSet$(E))(equals, hashCode, isValidKey);
       }
       static identity() {
         return new (_IdentityHashSet$(E))();
       }
       static from(elements) {
         let result = HashSet$(E).new();
-        for (let e of dart.as(elements, core.Iterable$(E)))
+        for (let e of elements) {
+          dart.as(e, E);
           result.add(e);
+        }
         return result;
       }
       [Symbol.iterator]() {
         return new dart.JsIterator(this.iterator);
       }
     }
     HashSet[dart.implements] = () => [core.Set$(E)];
     dart.setSignature(HashSet, {
       constructors: () => ({
         new: [HashSet$(E), [], {equals: dart.functionType(core.bool, [E, E]), hashCode: dart.functionType(core.int, [E]), isValidKey: dart.functionType(core.bool, [core.Object])}],
@@ skipping 2152 matching lines @@
   const DoubleLinkedQueue$ = dart.generic(function(E) {
     class DoubleLinkedQueue extends IterableBase$(E) {
       DoubleLinkedQueue() {
         this[_sentinel] = null;
         this[_elementCount] = 0;
         super.IterableBase();
         this[_sentinel] = new (_DoubleLinkedQueueEntrySentinel$(E))();
       }
       static from(elements) {
         let list = new (DoubleLinkedQueue$(E))();
-        for (let e of dart.as(elements, core.Iterable$(E))) {
+        for (let e of elements) {
+          dart.as(e, E);
           list.addLast(e);
         }
         return dart.as(list, DoubleLinkedQueue$(E));
       }
       get length() {
         return this[_elementCount];
       }
       addLast(value) {
         dart.as(value, E);
         this[_sentinel].prepend(value);
@@ skipping 199 matching lines @@
           let sourceList = elements;
           queue[_table][dartx.setRange](0, length, dart.as(sourceList, core.Iterable$(E)), 0);
           queue[_tail] = length;
           return queue;
         } else {
           let capacity = ListQueue$()._INITIAL_CAPACITY;
           if (dart.is(elements, _internal.EfficientLength)) {
             capacity = elements[dartx.length];
           }
           let result = new (ListQueue$(E))(capacity);
-          for (let element of dart.as(elements, core.Iterable$(E))) {
+          for (let element of elements) {
+            dart.as(element, E);
             result.addLast(element);
           }
           return result;
         }
       }
       get iterator() {
         return new (_ListQueueIterator$(E))(this);
       }
       forEach(action) {
         dart.as(action, dart.functionType(dart.void, [E]));
@@ skipping 500 matching lines @@
     return _SplayTree;
   });
   let _SplayTree = _SplayTree$();
   const _comparator = Symbol('_comparator');
   const _validKey = Symbol('_validKey');
   const SplayTreeMap$ = dart.generic(function(K, V) {
     class SplayTreeMap extends _SplayTree$(K) {
       SplayTreeMap(compare, isValidKey) {
         if (compare === void 0) compare = null;
         if (isValidKey === void 0) isValidKey = null;
-        this[_comparator] = compare == null ? core.Comparable.compare : compare;
+        this[_comparator] = dart.as(compare == null ? core.Comparable.compare : compare, core.Comparator$(K));
         this[_validKey] = isValidKey != null ? isValidKey : dart.fn(v => dart.is(v, K), core.bool, [core.Object]);
         super._SplayTree();
       }
       static from(other, compare, isValidKey) {
         if (compare === void 0) compare = null;
         if (isValidKey === void 0) isValidKey = null;
         let result = new (SplayTreeMap$(K, V))();
         other[dartx.forEach](dart.fn((k, v) => {
           result.set(dart.as(k, K), dart.as(v, V));
         }, dart.void, [dart.dynamic, dart.dynamic]));
@@ skipping 413 matching lines @@
     });
     return _SplayTreeNodeIterator;
   });
   let _SplayTreeNodeIterator = _SplayTreeNodeIterator$();
   const _clone = Symbol('_clone');
   const SplayTreeSet$ = dart.generic(function(E) {
     class SplayTreeSet extends dart.mixin(_SplayTree$(E), IterableMixin$(E), SetMixin$(E)) {
       SplayTreeSet(compare, isValidKey) {
         if (compare === void 0) compare = null;
         if (isValidKey === void 0) isValidKey = null;
-        this[_comparator] = compare == null ? core.Comparable.compare : compare;
+        this[_comparator] = dart.as(compare == null ? core.Comparable.compare : compare, core.Comparator$(E));
         this[_validKey] = isValidKey != null ? isValidKey : dart.fn(v => dart.is(v, E), core.bool, [core.Object]);
         super._SplayTree();
       }
       static from(elements, compare, isValidKey) {
         if (compare === void 0) compare = null;
         if (isValidKey === void 0) isValidKey = null;
         let result = new (SplayTreeSet$(E))(compare, isValidKey);
-        for (let element of dart.as(elements, core.Iterable$(E))) {
+        for (let element of elements) {
+          dart.as(element, E);
           result.add(element);
         }
         return result;
       }
       [_compare](e1, e2) {
         dart.as(e1, E);
         dart.as(e2, E);
         return this[_comparator](e1, e2);
       }
       get iterator() {
@@ skipping 1999 matching lines @@
   exports.LinkedHashMapKeyIterable$ = LinkedHashMapKeyIterable$;
   exports.LinkedHashMapKeyIterable = LinkedHashMapKeyIterable;
   exports.LinkedHashMapKeyIterator$ = LinkedHashMapKeyIterator$;
   exports.LinkedHashMapKeyIterator = LinkedHashMapKeyIterator;
   exports.HashSetIterator$ = HashSetIterator$;
   exports.HashSetIterator = HashSetIterator;
   exports.LinkedHashSetCell = LinkedHashSetCell;
   exports.LinkedHashSetIterator$ = LinkedHashSetIterator$;
   exports.LinkedHashSetIterator = LinkedHashSetIterator;
 });