fix some errors in our SDK, mostly around numbers

lib/runtime/dart/_native_typed_data.js

 dart_library.library('dart/_native_typed_data', null, /* Imports */[
   "dart_runtime/dart",
   'dart/core',
   'dart/typed_data',
   'dart/_js_helper',
   'dart/collection',
   'dart/_internal',
   'dart/_interceptors',
   'dart/math'
 ], /* Lazy imports */[
@@ skipping 721 matching lines @@
       }
       this.set(source, start);
     }
   }
   NativeTypedArray[dart.implements] = () => [_js_helper.JavaScriptIndexingBehavior];
   dart.setSignature(NativeTypedArray, {
     methods: () => ({[_setRangeFast]: [dart.void, [core.int, core.int, NativeTypedArray, core.int]]})
   });
   class NativeTypedArrayOfDouble extends dart.mixin(NativeTypedArray, collection.ListMixin$(core.double), _internal.FixedLengthListMixin$(core.double)) {
     get length() {
-      return dart.as(this.length, core.int);
+      return this.length;
     }
     get(index) {
       this[_checkIndex](index, this.length);
       return this[index];
     }
     set(index, value) {
       this[_checkIndex](index, this.length);
       this[index] = value;
       return value;
     }
@@ skipping 10 matching lines @@
   dart.setSignature(NativeTypedArrayOfDouble, {
     methods: () => ({
       get: [core.double, [core.int]],
       set: [dart.void, [core.int, core.num]],
       setRange: [dart.void, [core.int, core.int, core.Iterable$(core.double)], [core.int]]
     })
   });
   dart.defineExtensionMembers(NativeTypedArrayOfDouble, ['get', 'set', 'setRange', 'length']);
   class NativeTypedArrayOfInt extends dart.mixin(NativeTypedArray, collection.ListMixin$(core.int), _internal.FixedLengthListMixin$(core.int)) {
     get length() {
-      return dart.as(this.length, core.int);
+      return this.length;
     }
     set(index, value) {
       this[_checkIndex](index, this.length);
       this[index] = value;
       return value;
     }
     setRange(start, end, iterable, skipCount) {
       if (skipCount === void 0)
         skipCount = 0;
       if (dart.is(iterable, NativeTypedArrayOfInt)) {
@@ skipping 281 matching lines @@
     }
     static view(buffer, offsetInBytes, length) {
       _checkViewArguments(buffer, offsetInBytes, length);
       return length == null ? NativeUint16List._create2(buffer, offsetInBytes) : NativeUint16List._create3(buffer, offsetInBytes, length);
     }
     get runtimeType() {
       return typed_data.Uint16List;
     }
     get(index) {
       this[_checkIndex](index, this.length);
-      return dart.as(this[index], core.int);
+      return this[index];
     }
     sublist(start, end) {
       if (end === void 0)
         end = null;
       end = this[_checkSublistArguments](start, end, this.length);
       let source = this.subarray(start, end);
       return NativeUint16List._create1(source);
     }
     static _create1(arg) {
       return dart.as(new Uint16Array(arg), NativeUint16List);
@@ skipping 34 matching lines @@
     }
     static view(buffer, offsetInBytes, length) {
       _checkViewArguments(buffer, offsetInBytes, length);
       return length == null ? NativeUint32List._create2(buffer, offsetInBytes) : NativeUint32List._create3(buffer, offsetInBytes, length);
     }
     get runtimeType() {
       return typed_data.Uint32List;
     }
     get(index) {
       this[_checkIndex](index, this.length);
-      return dart.as(this[index], core.int);
+      return this[index];
     }
     sublist(start, end) {
       if (end === void 0)
         end = null;
       end = this[_checkSublistArguments](start, end, this.length);
       let source = this.subarray(start, end);
       return NativeUint32List._create1(source);
     }
     static _create1(arg) {
       return dart.as(new Uint32Array(arg), NativeUint32List);
@@ skipping 33 matching lines @@
       return NativeUint8ClampedList._create1(_ensureNativeList(elements));
     }
     static view(buffer, offsetInBytes, length) {
       _checkViewArguments(buffer, offsetInBytes, length);
       return length == null ? NativeUint8ClampedList._create2(buffer, offsetInBytes) : NativeUint8ClampedList._create3(buffer, offsetInBytes, length);
     }
     get runtimeType() {
       return typed_data.Uint8ClampedList;
     }
     get length() {
-      return dart.as(this.length, core.int);
+      return this.length;
     }
     get(index) {
       this[_checkIndex](index, this.length);
-      return dart.as(this[index], core.int);
+      return this[index];
     }
     sublist(start, end) {
       if (end === void 0)
         end = null;
       end = this[_checkSublistArguments](start, end, this.length);
       let source = this.subarray(start, end);
       return NativeUint8ClampedList._create1(source);
     }
     static _create1(arg) {
       return dart.as(new Uint8ClampedArray(arg), NativeUint8ClampedList);
@@ skipping 33 matching lines @@
       return NativeUint8List._create1(_ensureNativeList(elements));
     }
     static view(buffer, offsetInBytes, length) {
       _checkViewArguments(buffer, offsetInBytes, length);
       return length == null ? NativeUint8List._create2(buffer, offsetInBytes) : NativeUint8List._create3(buffer, offsetInBytes, length);
     }
     get runtimeType() {
       return typed_data.Uint8List;
     }
     get length() {
-      return dart.as(this.length, core.int);
+      return this.length;
     }
     get(index) {
       this[_checkIndex](index, this.length);
-      return dart.as(this[index], core.int);
+      return this[index];
     }
     sublist(start, end) {
       if (end === void 0)
         end = null;
       end = this[_checkSublistArguments](start, end, this.length);
       let source = this.subarray(start, end);
       return NativeUint8List._create1(source);
     }
     static _create1(arg) {
       return dart.as(new Uint8Array(arg), NativeUint8List);
@@ skipping 28 matching lines @@
   class NativeFloat32x4 extends core.Object {
     static _truncate(x) {
       NativeFloat32x4._list.set(0, dart.as(x, core.num));
       return NativeFloat32x4._list.get(0);
     }
     NativeFloat32x4(x, y, z, w) {
       this.x = dart.as(NativeFloat32x4._truncate(x), core.double);
       this.y = dart.as(NativeFloat32x4._truncate(y), core.double);
       this.z = dart.as(NativeFloat32x4._truncate(z), core.double);
       this.w = dart.as(NativeFloat32x4._truncate(w), core.double);
-      if (!dart.is(x, core.num))
+      if (!(typeof x == 'number'))
         dart.throw(new core.ArgumentError(x));
-      if (!dart.is(y, core.num))
+      if (!(typeof y == 'number'))
         dart.throw(new core.ArgumentError(y));
-      if (!dart.is(z, core.num))
+      if (!(typeof z == 'number'))
         dart.throw(new core.ArgumentError(z));
-      if (!dart.is(w, core.num))
+      if (!(typeof w == 'number'))
         dart.throw(new core.ArgumentError(w));
     }
     splat(v) {
       this.NativeFloat32x4(v, v, v, v);
     }
     zero() {
       this._truncated(0.0, 0.0, 0.0, 0.0);
     }
     static fromInt32x4Bits(i) {
       NativeFloat32x4._uint32view.set(0, i.x);
@@ skipping 485 matching lines @@
   });
   dart.defineLazyProperties(NativeInt32x4, {
     get _list() {
       return NativeInt32List.new(4);
     }
   });
   class NativeFloat64x2 extends core.Object {
     NativeFloat64x2(x, y) {
       this.x = x;
       this.y = y;
-      if (!dart.is(this.x, core.num))
+      if (!(typeof this.x == 'number'))
         dart.throw(new core.ArgumentError(this.x));
-      if (!dart.is(this.y, core.num))
+      if (!(typeof this.y == 'number'))
         dart.throw(new core.ArgumentError(this.y));
     }
     splat(v) {
       this.NativeFloat64x2(v, v);
     }
     zero() {
       this.splat(0.0);
     }
     fromFloat32x4(v) {
       this.NativeFloat64x2(v.x, v.y);
@@ skipping 41 matching lines @@
     }
     get signMask() {
       let view = NativeFloat64x2._uint32View;
       NativeFloat64x2._list.set(0, this.x);
       NativeFloat64x2._list.set(1, this.y);
       let mx = (dart.notNull(view.get(1)) & 2147483648) >> 31;
       let my = (dart.notNull(view.get(3)) & 2147483648) >> 31;
       return dart.notNull(mx) | dart.notNull(my) << 1;
     }
     withX(x) {
-      if (!dart.is(x, core.num))
+      if (!(typeof x == 'number'))
         dart.throw(new core.ArgumentError(x));
       return new NativeFloat64x2._doubles(x, this.y);
     }
     withY(y) {
-      if (!dart.is(y, core.num))
+      if (!(typeof y == 'number'))
         dart.throw(new core.ArgumentError(y));
       return new NativeFloat64x2._doubles(this.x, y);
     }
     min(other) {
       return new NativeFloat64x2._doubles(dart.notNull(this.x) < dart.notNull(other.x) ? this.x : other.x, dart.notNull(this.y) < dart.notNull(other.y) ? this.y : other.y);
     }
     max(other) {
       return new NativeFloat64x2._doubles(dart.notNull(this.x) > dart.notNull(other.x) ? this.x : other.x, dart.notNull(this.y) > dart.notNull(other.y) ? this.y : other.y);
     }
     sqrt() {
@@ skipping 55 matching lines @@
   exports.NativeInt32List = NativeInt32List;
   exports.NativeInt8List = NativeInt8List;
   exports.NativeUint16List = NativeUint16List;
   exports.NativeUint32List = NativeUint32List;
   exports.NativeUint8ClampedList = NativeUint8ClampedList;
   exports.NativeUint8List = NativeUint8List;
   exports.NativeFloat32x4 = NativeFloat32x4;
   exports.NativeInt32x4 = NativeInt32x4;
   exports.NativeFloat64x2 = NativeFloat64x2;
 });