Make implicit casts hints

tool/sdk_expected_errors.txt

Index: tool/sdk_expected_errors.txt
diff --git a/tool/sdk_expected_errors.txt b/tool/sdk_expected_errors.txt
index 26168c3220ef9c9c1280ed2e5367bc2ecb3be279..6af1a26cfe7fe4e5f12b6f5872a4dbbabaa2673c 100644
--- a/tool/sdk_expected_errors.txt
+++ b/tool/sdk_expected_errors.txt
@@ -2,24 +2,24 @@ severe: [AnalyzerMessage] Classes cannot implement 'bool' (dart:_interceptors, l
 severe: [AnalyzerMessage] Classes cannot implement 'num' (dart:_interceptors/js_number.dart, line 16, col 47)
 severe: [AnalyzerMessage] The return type 'JSNumber' is not a 'double', as defined by the method 'toDouble' (dart:_interceptors/js_number.dart, line 110, col 17)
 severe: [StaticTypeError] Type check failed: this (JSNumber) is not of type double (dart:_interceptors/js_number.dart, line 110, col 17)
-severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.sign (() → num) is not a subtype of int.sign (() → int). (dart:_interceptors/js_number.dart, line 349, col 13)
-severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.& ((num) → num) is not a subtype of int.& ((int) → int). (dart:_interceptors/js_number.dart, line 349, col 13)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.abs (() → num) is not a subtype of int.abs (() → int). (dart:_interceptors/js_number.dart, line 349, col 13)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.unary- (() → num) is not a subtype of int.unary- (() → int). (dart:_interceptors/js_number.dart, line 349, col 13)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.<< ((num) → num) is not a subtype of int.<< ((int) → int). (dart:_interceptors/js_number.dart, line 349, col 13)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.>> ((num) → num) is not a subtype of int.>> ((int) → int). (dart:_interceptors/js_number.dart, line 349, col 13)
+severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.& ((num) → num) is not a subtype of int.& ((int) → int). (dart:_interceptors/js_number.dart, line 349, col 13)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.| ((num) → num) is not a subtype of int.| ((int) → int). (dart:_interceptors/js_number.dart, line 349, col 13)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.^ ((num) → num) is not a subtype of int.^ ((int) → int). (dart:_interceptors/js_number.dart, line 349, col 13)
+severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.sign (() → num) is not a subtype of int.sign (() → int). (dart:_interceptors/js_number.dart, line 349, col 13)
 severe: [AnalyzerMessage] Classes cannot implement 'int' (dart:_interceptors/js_number.dart, line 349, col 41)
 severe: [AnalyzerMessage] Classes cannot implement 'double' (dart:_interceptors/js_number.dart, line 349, col 46)
-severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.unary- (() → num) is not a subtype of double.unary- (() → double). (dart:_interceptors/js_number.dart, line 420, col 16)
-severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.sign (() → num) is not a subtype of double.sign (() → double). (dart:_interceptors/js_number.dart, line 420, col 16)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.remainder ((num) → num) is not a subtype of double.remainder ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.abs (() → num) is not a subtype of double.abs (() → double). (dart:_interceptors/js_number.dart, line 420, col 16)
+severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.unary- (() → num) is not a subtype of double.unary- (() → double). (dart:_interceptors/js_number.dart, line 420, col 16)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.+ ((num) → num) is not a subtype of double.+ ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.- ((num) → num) is not a subtype of double.- ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.* ((num) → num) is not a subtype of double.* ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
 severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.% ((num) → num) is not a subtype of double.% ((num) → double). (dart:_interceptors/js_number.dart, line 420, col 16)
+severe: [InvalidMethodOverride] Base class introduces an invalid override. The type of JSNumber.sign (() → num) is not a subtype of double.sign (() → double). (dart:_interceptors/js_number.dart, line 420, col 16)
 severe: [AnalyzerMessage] Classes cannot implement 'double' (dart:_interceptors/js_number.dart, line 420, col 44)
 severe: [AnalyzerMessage] Classes cannot implement 'String' (dart:_interceptors/js_string.dart, line 14, col 47)
 severe: [StaticTypeError] Type check failed: s += s (String) is not of type JSString (dart:_interceptors/js_string.dart, line 346, col 7)
@@ -42,15 +42,6 @@ severe: [AnalyzerMessage] The getter '_validKey' is not defined for the class '_
 warning: [DownCastComposite] doneHandlers (dynamic) will need runtime check to cast to type Iterable<SendPort> (dart:_isolate_helper, line 574, col 29)
 warning: [DownCastComposite] args (dynamic) will need runtime check to cast to type List<String> (dart:_isolate_helper, line 839, col 37)
 warning: [DownCastComposite] msg['args'] (dynamic) will need runtime check to cast to type List<String> (dart:_isolate_helper, line 886, col 11)
-warning: [DownCastImplicit] indexable (JSIndexable) will need runtime check to cast to type JSArray<dynamic> (dart:_isolate_helper/isolate_serialization.dart, line 89, col 38)
-warning: [DownCastImplicit] serializeTearOff (Function) will need runtime check to cast to type (dynamic) → dynamic (dart:_isolate_helper/isolate_serialization.dart, line 120, col 24)
-warning: [DownCastImplicit] serializeTearOff (Function) will need runtime check to cast to type (dynamic) → dynamic (dart:_isolate_helper/isolate_serialization.dart, line 121, col 26)
-warning: [DownCastImplicit] fields (List<dynamic>) will need runtime check to cast to type JSArray<dynamic> (dart:_isolate_helper/isolate_serialization.dart, line 172, col 52)
-warning: [DownCastImplicit] result (List<dynamic>) will need runtime check to cast to type JSArray<dynamic> (dart:_isolate_helper/isolate_serialization.dart, line 250, col 58)
-warning: [DownCastImplicit] result (List<dynamic>) will need runtime check to cast to type JSArray<dynamic> (dart:_isolate_helper/isolate_serialization.dart, line 258, col 61)
-warning: [DownCastImplicit] result (List<dynamic>) will need runtime check to cast to type JSArray<dynamic> (dart:_isolate_helper/isolate_serialization.dart, line 266, col 36)
-warning: [DownCastImplicit] result (List<dynamic>) will need runtime check to cast to type JSArray<dynamic> (dart:_isolate_helper/isolate_serialization.dart, line 275, col 58)
-warning: [DownCastImplicit] fields (List<dynamic>) will need runtime check to cast to type JSArray<dynamic> (dart:_isolate_helper/isolate_serialization.dart, line 357, col 29)
 warning: [DownCastComposite] JS('var', r'#.pop()', this) (dynamic) will need runtime check to cast to type E (dart:_interceptors/js_array.dart, line 80, col 12)
 warning: [DownCastComposite] JS('', '#[#]', this, i) (dynamic) will need runtime check to cast to type E (dart:_interceptors/js_array.dart, line 125, col 9)
 warning: [DownCastComposite] IterableMixinWorkaround.reduce(this, combine) (dynamic) will need runtime check to cast to type E (dart:_interceptors/js_array.dart, line 161, col 12)
@@ -58,33 +49,14 @@ warning: [DownCastComposite] IterableMixinWorkaround.firstWhere(this, test, orEl
 warning: [DownCastComposite] IterableMixinWorkaround.lastWhereList(this, test, orElse) (dynamic) will need runtime check to cast to type E (dart:_interceptors/js_array.dart, line 173, col 12)
 warning: [DownCastComposite] IterableMixinWorkaround.singleWhere(this, test) (dynamic) will need runtime check to cast to type E (dart:_interceptors/js_array.dart, line 177, col 12)
 warning: [DownCastComposite] JS('var', '#[#]', this, index) (dynamic) will need runtime check to cast to type E (dart:_interceptors/js_array.dart, line 313, col 12)
-warning: [DownCastImplicit] JS('num', r'parseInt(#, 16)', source) (num) will need runtime check to cast to type int (dart:_js_helper, line 87, col 18)
-warning: [DownCastImplicit] JS('num', r'parseInt(#, 10)', source) (num) will need runtime check to cast to type int (dart:_js_helper, line 91, col 18)
-warning: [DownCastImplicit] JS('num', r'parseInt(#, 10)', source) (num) will need runtime check to cast to type int (dart:_js_helper, line 103, col 18)
-warning: [DownCastImplicit] JS('num', r'parseInt(#, #)', source, radix) (num) will need runtime check to cast to type int (dart:_js_helper, line 135, col 12)
-warning: [DownCastImplicit] result (num) will need runtime check to cast to type double (dart:_js_helper, line 159, col 16)
-warning: [DownCastImplicit] result (num) will need runtime check to cast to type double (dart:_js_helper, line 163, col 12)
-warning: [DownCastImplicit] 0xd800 + ((((i - 0x10000) >> 10) & 0x3ff)) (num) will need runtime check to cast to type int (dart:_js_helper, line 250, col 15)
-warning: [DownCastImplicit] 0xdc00 + (i & 0x3ff) (num) will need runtime check to cast to type int (dart:_js_helper, line 251, col 15)
 warning: [DownCastComposite] charCodes (dynamic) will need runtime check to cast to type List<int> (dart:_js_helper, line 265, col 31)
 warning: [DownCastComposite] JS('', '#.value', ret) (dynamic) will need runtime check to cast to type E (dart:_js_helper, line 780, col 16)
-warning: [DownCastImplicit] JS('num', r'Math.ceil(#)', this) (num) will need runtime check to cast to type double (dart:_interceptors/js_number.dart, line 83, col 28)
-warning: [DownCastImplicit] JS('num', r'Math.floor(#)', this) (num) will need runtime check to cast to type double (dart:_interceptors/js_number.dart, line 85, col 29)
-warning: [DownCastImplicit] JS('num', r'-Math.round(-#)', this) (num) will need runtime check to cast to type double (dart:_interceptors/js_number.dart, line 89, col 14)
-warning: [DownCastImplicit] JS('num', r'Math.round(#)', this) (num) will need runtime check to cast to type double (dart:_interceptors/js_number.dart, line 91, col 14)
-warning: [DownCastImplicit] this & ((1 << width) - 1) (num) will need runtime check to cast to type int (dart:_interceptors/js_number.dart, line 357, col 12)
-warning: [DownCastImplicit] (this & (signMask - 1)) - (this & signMask) (num) will need runtime check to cast to type int (dart:_interceptors/js_number.dart, line 362, col 12)
 warning: [DownCastComposite] JS('JSExtendableArray', r'#.split(#)', this, pattern) (dynamic) will need runtime check to cast to type List<String> (dart:_interceptors/js_string.dart, line 86, col 14)
 warning: [DownCastComposite] JS('JSExtendableArray', r'#.split(#)', this, re) (dynamic) will need runtime check to cast to type List<String> (dart:_interceptors/js_string.dart, line 89, col 14)
-warning: [DownCastImplicit] _storage.sublist(start * 4, end * 4) (List<double>) will need runtime check to cast to type NativeFloat32List (dart:_native_typed_data, line 201, col 9)
-warning: [DownCastImplicit] _storage.sublist(start * 4, end * 4) (List<int>) will need runtime check to cast to type Int32List (dart:_native_typed_data, line 311, col 9)
-warning: [DownCastImplicit] _storage.sublist(start * 2, end * 2) (List<double>) will need runtime check to cast to type NativeFloat64List (dart:_native_typed_data, line 415, col 9)
-warning: [DownCastImplicit] length == null ? _create2(buffer, offsetInBytes) : _create3(buffer, offsetInBytes, length) (Int8List) will need runtime check to cast to type NativeInt8List (dart:_native_typed_data, line 1106, col 12)
 warning: [DownCastComposite] JS('JSExtendableArray|Null', r'#.exec(#)', _nativeRegExp, checkString(string)) (dynamic) will need runtime check to cast to type List<String> (dart:_js_helper/regexp_helper.dart, line 108, col 22)
 warning: [DownCastComposite] match (List<dynamic>) will need runtime check to cast to type List<String> (dart:_js_helper/regexp_helper.dart, line 140, col 43)
 warning: [DownCastComposite] match (List<dynamic>) will need runtime check to cast to type List<String> (dart:_js_helper/regexp_helper.dart, line 152, col 43)
 warning: [DownCastComposite] pattern.allMatches(receiver) (dynamic) will need runtime check to cast to type Iterable<Match> (dart:_js_helper/string_helper.dart, line 137, col 23)
-warning: [DownCastImplicit] errorHandler (Function) will need runtime check to cast to type (dynamic) → dynamic (dart:async/async_error.dart, line 20, col 39)
 warning: [DownCastComposite] controller (_StreamControllerLifecycle<dynamic>) will need runtime check to cast to type _StreamControllerLifecycle<T> (dart:async/broadcast_stream_controller.dart, line 8, col 67)
 warning: [DownCastComposite] controller (_StreamControllerLifecycle<dynamic>) will need runtime check to cast to type _StreamControllerLifecycle<T> (dart:async/broadcast_stream_controller.dart, line 36, col 15)
 warning: [DownCastComposite] super._controller (_StreamControllerLifecycle<T>) will need runtime check to cast to type _BroadcastStreamController<T> (dart:async/broadcast_stream_controller.dart, line 40, col 52)
@@ -99,9 +71,7 @@ warning: [DownCastComposite] link (_BroadcastSubscriptionLink) will need runtime
 warning: [DownCastComposite] result (_Future<dynamic>) will need runtime check to cast to type Future<T> (dart:async/future.dart, line 123, col 12)
 warning: [DownCastComposite] result (_Future<dynamic>) will need runtime check to cast to type Future<T> (dart:async/future.dart, line 149, col 12)
 warning: [DownCastComposite] result (_Future<dynamic>) will need runtime check to cast to type Future<T> (dart:async/future.dart, line 233, col 12)
-warning: [DownCastImplicit] callback (Function) will need runtime check to cast to type (dynamic) → dynamic (dart:async/future_impl.dart, line 112, col 12)
 warning: [DownCastComposite] callback (Function) will need runtime check to cast to type (dynamic) → bool (dart:async/future_impl.dart, line 117, col 12)
-warning: [DownCastImplicit] callback (Function) will need runtime check to cast to type () → dynamic (dart:async/future_impl.dart, line 121, col 12)
 warning: [DownCastComposite] result._zone.registerUnaryCallback(f) ((dynamic) → dynamic) will need runtime check to cast to type (T) → dynamic (dart:async/future_impl.dart, line 208, col 11)
 warning: [DownCastComposite] result._zone.registerUnaryCallback(test) ((dynamic) → dynamic) will need runtime check to cast to type (dynamic) → bool (dart:async/future_impl.dart, line 221, col 32)
 warning: [DownCastComposite] result (_Future<dynamic>) will need runtime check to cast to type Future<T> (dart:async/future_impl.dart, line 233, col 12)
@@ -111,7 +81,6 @@ warning: [DownCastComposite] value (dynamic) will need runtime check to cast to
 warning: [DownCastComposite] value (dynamic) will need runtime check to cast to type Future<T> (dart:async/future_impl.dart, line 386, col 31)
 warning: [DownCastComposite] typedFuture (Future<T>) will need runtime check to cast to type _Future<T> (dart:async/future_impl.dart, line 388, col 33)
 warning: [DownCastComposite] value (dynamic) will need runtime check to cast to type T (dart:async/future_impl.dart, line 407, col 22)
-warning: [DownCastImplicit] errorCallback (Function) will need runtime check to cast to type (dynamic) → dynamic (dart:async/future_impl.dart, line 515, col 54)
 warning: [DownCastComposite] callback (dynamic) will need runtime check to cast to type () → void (dart:async/schedule_microtask.dart, line 66, col 61)
 warning: [DownCastComposite] callback (dynamic) will need runtime check to cast to type () → void (dart:async/schedule_microtask.dart, line 71, col 60)
 warning: [DownCastComposite] callback (dynamic) will need runtime check to cast to type () → void (dart:async/schedule_microtask.dart, line 84, col 55)
@@ -138,8 +107,6 @@ warning: [DownCastComposite] subscription (_ControllerSubscription<dynamic>) wil
 warning: [DownCastComposite] controller (_StreamController<dynamic>) will need runtime check to cast to type _EventSink<T> (dart:async/stream_controller.dart, line 798, col 15)
 warning: [DownCastComposite] _nullDataHandler ((dynamic) → void) will need runtime check to cast to type (T) → void (dart:async/stream_impl.dart, line 153, col 42)
 warning: [DownCastComposite] _zone.registerUnaryCallback(handleData) ((dynamic) → dynamic) will need runtime check to cast to type (T) → void (dart:async/stream_impl.dart, line 154, col 15)
-warning: [DownCastImplicit] _onError (Function) will need runtime check to cast to type (dynamic, dynamic) → dynamic (dart:async/stream_impl.dart, line 358, col 32)
-warning: [DownCastImplicit] _onError (Function) will need runtime check to cast to type (dynamic) → dynamic (dart:async/stream_impl.dart, line 360, col 31)
 warning: [DownCastComposite] subscription (StreamSubscription<dynamic>) will need runtime check to cast to type StreamSubscription<T> (dart:async/stream_impl.dart, line 476, col 12)
 warning: [DownCastComposite] new _BufferingStreamSubscription(onData, onError, onDone, cancelOnError).._setPendingEvents(_pending()) (_BufferingStreamSubscription<dynamic>) will need runtime check to cast to type StreamSubscription<T> (dart:async/stream_impl.dart, line 515, col 12)
 warning: [DownCastComposite] Zone.current.registerUnaryCallback(onListenHandler) ((dynamic) → dynamic) will need runtime check to cast to type (StreamSubscription<dynamic>) → void (dart:async/stream_impl.dart, line 813, col 28)
@@ -158,10 +125,7 @@ warning: [UninferredClosure] (EventSink<T> outputSink) {if (handleData == null)
 warning: [DownCastComposite] _defaultHandleData ((dynamic, EventSink<dynamic>) → void) will need runtime check to cast to type (S, EventSink<T>) → void (dart:async/stream_transformers.dart, line 234, col 48)
 warning: [DownCastComposite] _defaultHandleError ((dynamic, StackTrace, EventSink<dynamic>) → void) will need runtime check to cast to type (Object, StackTrace, EventSink<T>) → void (dart:async/stream_transformers.dart, line 235, col 50)
 warning: [DownCastComposite] Zone.current.bindUnaryCallback(callback, runGuarded: true) ((dynamic) → dynamic) will need runtime check to cast to type (Timer) → void (dart:async/timer.dart, line 80, col 19)
-warning: [DownCastImplicit] implementationZone (Zone) will need runtime check to cast to type _Zone (dart:async/zone.dart, line 845, col 57)
 warning: [DownCastComposite] zone.bindUnaryCallback(callback) ((dynamic) → dynamic) will need runtime check to cast to type (Timer) → void (dart:async/zone.dart, line 962, col 16)
-warning: [DownCastImplicit] zone (Zone) will need runtime check to cast to type _Zone (dart:async/zone.dart, line 999, col 26)
-warning: [DownCastImplicit] onError (Function) will need runtime check to cast to type (dynamic) → dynamic (dart:async/zone.dart, line 1228, col 37)
 warning: [DownCastComposite] JS('var', '#.splice(#, 2)[1]', bucket, index) (dynamic) will need runtime check to cast to type V (dart:collection, line 179, col 12)
 warning: [DownCastComposite] key (dynamic) will need runtime check to cast to type K (dart:collection, line 193, col 14)
 warning: [DownCastComposite] _getTableEntry(table, key) (dynamic) will need runtime check to cast to type V (dart:collection, line 261, col 17)
@@ -211,7 +175,6 @@ warning: [DownCastComposite] _next (_LinkedListLink) will need runtime check to
 warning: [DownCastComposite] current (_LinkedListLink) will need runtime check to cast to type E (dart:collection/linked_list.dart, line 134, col 14)
 warning: [DownCastComposite] _next (_LinkedListLink) will need runtime check to cast to type E (dart:collection/linked_list.dart, line 192, col 16)
 warning: [DownCastComposite] _next (_LinkedListLink) will need runtime check to cast to type E (dart:collection/linked_list.dart, line 249, col 16)
-warning: [DownCastImplicit] iterable (Iterable<E>) will need runtime check to cast to type List<dynamic> (dart:collection/list.dart, line 365, col 19)
 warning: [DownCastComposite] otherList[otherStart + i] (dynamic) will need runtime check to cast to type E (dart:collection/list.dart, line 377, col 27)
 warning: [DownCastComposite] otherList[otherStart + i] (dynamic) will need runtime check to cast to type E (dart:collection/list.dart, line 381, col 27)
 warning: [DownCastComposite] _map[_map.keys.first] (dynamic) will need runtime check to cast to type V (dart:collection/maps.dart, line 122, col 18)
@@ -239,12 +202,8 @@ warning: [DownCastComposite] mapRoot.value (dynamic) will need runtime check to
 warning: [DownCastComposite] mapRoot.value (dynamic) will need runtime check to cast to type V (dart:collection/splay_tree.dart, line 363, col 14)
 warning: [DownCastComposite] nodes.current (_SplayTreeNode<K>) will need runtime check to cast to type _SplayTreeMapNode<K, V> (dart:collection/splay_tree.dart, line 394, col 38)
 warning: [DownCastComposite] key (Object) will need runtime check to cast to type K (dart:collection/splay_tree.dart, line 408, col 37)
-warning: [DownCastImplicit] node.right (_SplayTreeNode<dynamic>) will need runtime check to cast to type _SplayTreeMapNode<dynamic, dynamic> (dart:collection/splay_tree.dart, line 420, col 41)
-warning: [DownCastImplicit] node.left (_SplayTreeNode<dynamic>) will need runtime check to cast to type _SplayTreeMapNode<dynamic, dynamic> (dart:collection/splay_tree.dart, line 421, col 16)
-warning: [DownCastImplicit] _root (_SplayTreeNode<K>) will need runtime check to cast to type _SplayTreeMapNode<dynamic, dynamic> (dart:collection/splay_tree.dart, line 425, col 18)
 warning: [DownCastComposite] _first.key (dynamic) will need runtime check to cast to type K (dart:collection/splay_tree.dart, line 441, col 12)
 warning: [DownCastComposite] _last.key (dynamic) will need runtime check to cast to type K (dart:collection/splay_tree.dart, line 449, col 12)
-warning: [DownCastImplicit] _currentNode (_SplayTreeNode<dynamic>) will need runtime check to cast to type _SplayTreeMapNode<dynamic, dynamic> (dart:collection/splay_tree.dart, line 545, col 22)
 warning: [DownCastComposite] setOrMap._comparator (dynamic) will need runtime check to cast to type (K, K) → int (dart:collection/splay_tree.dart, line 610, col 29)
 warning: [DownCastComposite] setOrMap._validKey (dynamic) will need runtime check to cast to type (Object) → bool (dart:collection/splay_tree.dart, line 610, col 51)
 warning: [DownCastComposite] node.key (dynamic) will need runtime check to cast to type K (dart:collection/splay_tree.dart, line 628, col 39)
@@ -260,49 +219,29 @@ warning: [DownCastComposite] element (Object) will need runtime check to cast to
 warning: [DownCastComposite] object (Object) will need runtime check to cast to type E (dart:collection/splay_tree.dart, line 779, col 39)
 warning: [DownCastComposite] object (Object) will need runtime check to cast to type E (dart:collection/splay_tree.dart, line 791, col 23)
 warning: [DownCastComposite] result (List<dynamic>) will need runtime check to cast to type List<int> (dart:convert/ascii.dart, line 96, col 12)
-warning: [DownCastImplicit] sink (Sink<List<int>>) will need runtime check to cast to type ByteConversionSink (dart:convert/ascii.dart, line 109, col 55)
 warning: [DownCastComposite] _first.encoder.fuse(_second.encoder) (Converter<S, dynamic>) will need runtime check to cast to type Converter<S, T> (dart:convert/codec.dart, line 87, col 34)
 warning: [DownCastComposite] _second.decoder.fuse(_first.decoder) (Converter<T, dynamic>) will need runtime check to cast to type Converter<T, S> (dart:convert/codec.dart, line 88, col 34)
-warning: [DownCastImplicit] key (Object) will need runtime check to cast to type String (dart:convert, line 176, col 45)
-warning: [DownCastImplicit] key (Object) will need runtime check to cast to type String (dart:convert, line 177, col 53)
-warning: [DownCastImplicit] key (Object) will need runtime check to cast to type String (dart:convert, line 233, col 36)
 warning: [DownCastComposite] JS('JSExtendableArray', '#', keys) (dynamic) will need runtime check to cast to type List<String> (dart:convert, line 311, col 12)
 warning: [DownCastComposite] _second.convert(_first.convert(input)) (dynamic) will need runtime check to cast to type T (dart:convert/converter.dart, line 58, col 25)
 warning: [DownCastComposite] byteStream.transform(decoder).fold(new StringBuffer(), (buffer, string) => buffer..write(string)).then((buffer) => buffer.toString()) (Future<dynamic>) will need runtime check to cast to type Future<String> (dart:convert/encoding.dart, line 14, col 12)
-warning: [DownCastImplicit] sink (Sink<String>) will need runtime check to cast to type StringConversionSink (dart:convert/html_escape.dart, line 79, col 38)
 warning: [DownCastComposite] toEncodable ((dynamic) → dynamic) will need runtime check to cast to type (Object) → Object (dart:convert/json.dart, line 142, col 28)
 warning: [DownCastComposite] _toEncodable ((dynamic) → dynamic) will need runtime check to cast to type (Object) → Object (dart:convert/json.dart, line 147, col 28)
-warning: [DownCastImplicit] _toEncodable (Function) will need runtime check to cast to type (dynamic) → dynamic (dart:convert/json.dart, line 243, col 48)
-warning: [DownCastImplicit] sink (Sink<String>) will need runtime check to cast to type StringConversionSink (dart:convert/json.dart, line 262, col 33)
 warning: [DownCastComposite] _toEncodable (Function) will need runtime check to cast to type (Object) → dynamic (dart:convert/json.dart, line 270, col 42)
 warning: [DownCastComposite] _toEncodable (Function) will need runtime check to cast to type (Object) → dynamic (dart:convert/json.dart, line 352, col 36)
-warning: [DownCastImplicit] _toEncodable (Function) will need runtime check to cast to type (dynamic) → dynamic (dart:convert/json.dart, line 425, col 51)
 warning: [DownCastComposite] _toEncodable (Function) will need runtime check to cast to type (Object) → dynamic (dart:convert/json.dart, line 455, col 53)
 warning: [DownCastComposite] object (dynamic) will need runtime check to cast to type Map<String, Object> (dart:convert/json.dart, line 715, col 16)
 warning: [DownCastComposite] _toEncodable (dynamic) will need runtime check to cast to type (Object) → Object (dart:convert/json.dart, line 817, col 60)
 warning: [DownCastComposite] toEncodable (dynamic) will need runtime check to cast to type (Object) → Object (dart:convert/json.dart, line 895, col 15)
 warning: [DownCastComposite] sink (Sink<dynamic>) will need runtime check to cast to type Sink<String> (dart:convert/line_splitter.dart, line 24, col 44)
-warning: [DownCastImplicit] sink (Sink<dynamic>) will need runtime check to cast to type StringConversionSink (dart:convert/line_splitter.dart, line 26, col 34)
-warning: [DownCastImplicit] sink (Sink<List<int>>) will need runtime check to cast to type ByteConversionSink (dart:convert/utf.dart, line 125, col 33)
-warning: [DownCastImplicit] symbol (Symbol) will need runtime check to cast to type Symbol (dart:core, line 206, col 69)
-warning: [DownCastImplicit] Primitives.dateNow() (num) will need runtime check to cast to type int (dart:core/date_time.dart, line 593, col 34)
-warning: [DownCastImplicit] inMinutes.remainder(MINUTES_PER_HOUR) (num) will need runtime check to cast to type int (dart:core/duration.dart, line 258, col 40)
-warning: [DownCastImplicit] inSeconds.remainder(SECONDS_PER_MINUTE) (num) will need runtime check to cast to type int (dart:core/duration.dart, line 259, col 40)
-warning: [DownCastImplicit] inMicroseconds.remainder(MICROSECONDS_PER_SECOND) (num) will need runtime check to cast to type int (dart:core/duration.dart, line 261, col 19)
 warning: [DownCastComposite] (generator != null) ? generator : _id (Function) will need runtime check to cast to type (int) → E (dart:core/iterable.dart, line 319, col 22)
 warning: [DownCastComposite] e (dynamic) will need runtime check to cast to type E (dart:core/list.dart, line 121, col 16)
 warning: [DownCastComposite] makeListFixedLength(list) (List<dynamic>) will need runtime check to cast to type List<E> (dart:core/list.dart, line 124, col 12)
-warning: [DownCastImplicit] (_stop == null) ? (_now() - _start) : (_stop - _start) (num) will need runtime check to cast to type int (dart:core/stopwatch.dart, line 102, col 12)
-warning: [DownCastImplicit] _currentCodePoint (num) will need runtime check to cast to type int (dart:core/string.dart, line 753, col 22)
-warning: [DownCastImplicit] _port (num) will need runtime check to cast to type int (dart:core/uri.dart, line 94, col 12)
-warning: [DownCastImplicit] this._port (num) will need runtime check to cast to type int (dart:core/uri.dart, line 893, col 14)
 warning: [DownCastComposite] _userinfoTable (List<dynamic>) will need runtime check to cast to type List<int> (dart:core/uri.dart, line 1131, col 45)
 warning: [DownCastComposite] _pathCharOrSlashTable (List<dynamic>) will need runtime check to cast to type List<int> (dart:core/uri.dart, line 1144, col 45)
 warning: [DownCastComposite] _pathCharTable (List<dynamic>) will need runtime check to cast to type List<int> (dart:core/uri.dart, line 1146, col 51)
 warning: [DownCastComposite] _queryCharTable (List<dynamic>) will need runtime check to cast to type List<int> (dart:core/uri.dart, line 1163, col 61)
 warning: [DownCastComposite] _queryCharTable (List<dynamic>) will need runtime check to cast to type List<int> (dart:core/uri.dart, line 1183, col 45)
 warning: [DownCastComposite] codeUnits (List<dynamic>) will need runtime check to cast to type Iterable<int> (dart:core/uri.dart, line 1278, col 37)
-warning: [DownCastImplicit] this._port (num) will need runtime check to cast to type int (dart:core/uri.dart, line 1494, col 22)
 warning: [DownCastComposite] _unreserved2396Table (List<dynamic>) will need runtime check to cast to type List<int> (dart:core/uri.dart, line 1754, col 23)
 warning: [DownCastComposite] _unreservedTable (List<dynamic>) will need runtime check to cast to type List<int> (dart:core/uri.dart, line 1793, col 9)
 warning: [DownCastComposite] _encodeFullTable (List<dynamic>) will need runtime check to cast to type List<int> (dart:core/uri.dart, line 1837, col 23)
@@ -325,16 +264,12 @@ warning: [DownCastComposite] test ((dynamic) → bool) will need runtime check t
 warning: [DownCastComposite] list (List<dynamic>) will need runtime check to cast to type Iterable<T> (dart:_internal/iterable.dart, line 997, col 40)
 warning: [DownCastComposite] list (List<dynamic>) will need runtime check to cast to type Iterable<T> (dart:_internal/iterable.dart, line 1033, col 35)
 warning: [DownCastComposite] l (List<dynamic>) will need runtime check to cast to type List<T> (dart:_internal/iterable.dart, line 1115, col 31)
-warning: [DownCastImplicit] key (Object) will need runtime check to cast to type int (dart:_internal/list.dart, line 251, col 59)
 warning: [DownCastComposite] IsolateNatives.spawnFunction(entryPoint, message, paused).then((msg) => new Isolate(msg[1], pauseCapability: msg[2], terminateCapability: msg[3])) (Future<dynamic>) will need runtime check to cast to type Future<Isolate> (dart:isolate, line 168, col 14)
 warning: [DownCastComposite] IsolateNatives.spawnUri(uri, args, message, paused).then((msg) => new Isolate(msg[1], pauseCapability: msg[2], terminateCapability: msg[3])) (Future<dynamic>) will need runtime check to cast to type Future<Isolate> (dart:isolate, line 234, col 14)
 warning: [DownCastComposite] _convertToJS ((dynamic) → dynamic) will need runtime check to cast to type (E) → dynamic (dart:js, line 325, col 44)
 warning: [DownCastComposite] super[index] (dynamic) will need runtime check to cast to type E (dart:js, line 358, col 12)
-warning: [DownCastImplicit] list (Object) will need runtime check to cast to type List<dynamic> (dart:js, line 394, col 24)
 warning: [DownCastComposite] callMethod('splice', [index, 1])[0] (dynamic) will need runtime check to cast to type E (dart:js, line 404, col 12)
 warning: [DownCastComposite] callMethod('pop') (dynamic) will need runtime check to cast to type E (dart:js, line 409, col 12)
-warning: [DownCastImplicit] ms (num) will need runtime check to cast to type int (dart:js, line 486, col 52)
-warning: [DownCastImplicit] rnd32.remainder(max) (num) will need runtime check to cast to type int (dart:math, line 426, col 16)
 warning: [DownCastComposite] x + other.x (num) will need runtime check to cast to type T (dart:math/point.dart, line 37, col 25)
 warning: [DownCastComposite] y + other.y (num) will need runtime check to cast to type T (dart:math/point.dart, line 37, col 38)
 warning: [DownCastComposite] x - other.x (num) will need runtime check to cast to type T (dart:math/point.dart, line 46, col 25)
@@ -370,4 +305,3 @@ warning: [DownCastComposite] min(a.y, b.y) (num) will need runtime check to cast
 warning: [DownCastComposite] max(a.y, b.y) - top (num) will need runtime check to cast to type T (dart:math/rectangle.dart, line 231, col 16)
 warning: [DownCastComposite] _clampToZero(width) (num) will need runtime check to cast to type T (dart:math/rectangle.dart, line 247, col 28)
 warning: [DownCastComposite] _clampToZero(height) (num) will need runtime check to cast to type T (dart:math/rectangle.dart, line 263, col 30)
-warning: [DownCastImplicit] (tm as ClassMirror).originalDeclaration (TypeMirror) will need runtime check to cast to type ClassMirror (dart:mirrors, line 171, col 10)