Remove hack for length access of typed arrays.

sdk/lib/typed_data/dart2js/typed_data_dart2js.dart

Index: sdk/lib/typed_data/dart2js/typed_data_dart2js.dart
===================================================================
--- sdk/lib/typed_data/dart2js/typed_data_dart2js.dart	(revision 30471)
+++ sdk/lib/typed_data/dart2js/typed_data_dart2js.dart	(working copy)
@@ -42,18 +42,6 @@
   final int lengthInBytes;
 }
 
-// TODO(12929): Remove this constant once V8 optimizes length access of
-// typed arrays. Firefox does not like accessing a named property of a
-// typed array, so we only use the new [:$dartCachedLength:] property in V8 and
-// Chrome.
-const fetchLength = const JS_CONST(r'''
-    ((typeof version == "function" && typeof os == "object" && "system" in os)
-    || (typeof navigator == "object"
-        && navigator.userAgent.indexOf('Chrome') != -1))
-        ? function(x) { return x.$dartCachedLength || x.length; }
-        : function(x) { return x.length; };
-''');
-
 /**
  * A typed view of a sequence of bytes.
  */
@@ -519,7 +507,7 @@
 
   static const int BYTES_PER_ELEMENT = 4;
 
-  int get length => JS("int", '#(#)', fetchLength, this);
+  int get length => JS("int", '#.length', this);
 
   num operator[](int index) {
     _checkIndex(index, length);
@@ -597,7 +585,7 @@
 
   static const int BYTES_PER_ELEMENT = 8;
 
-  int get length => JS("int", '#(#)', fetchLength, this);
+  int get length => JS("int", '#.length', this);
 
   num operator[](int index) {
     _checkIndex(index, length);
@@ -676,7 +664,7 @@
 
   static const int BYTES_PER_ELEMENT = 2;
 
-  int get length => JS("int", '#(#)', fetchLength, this);
+  int get length => JS("int", '#.length', this);
 
   int operator[](int index) {
     _checkIndex(index, length);
@@ -751,7 +739,7 @@
 
   static const int BYTES_PER_ELEMENT = 4;
 
-  int get length => JS("int", '#(#)', fetchLength, this);
+  int get length => JS("int", '#.length', this);
 
   int operator[](int index) {
     _checkIndex(index, length);
@@ -823,7 +811,7 @@
 
   static const int BYTES_PER_ELEMENT = 1;
 
-  int get length => JS("int", '#(#)', fetchLength, this);
+  int get length => JS("int", '#.length', this);
 
   int operator[](int index) {
     _checkIndex(index, length);
@@ -899,7 +887,7 @@
 
   static const int BYTES_PER_ELEMENT = 2;
 
-  int get length => JS("int", '#(#)', fetchLength, this);
+  int get length => JS("int", '#.length', this);
 
   int operator[](int index) {
     _checkIndex(index, length);
@@ -975,7 +963,7 @@
 
   static const int BYTES_PER_ELEMENT = 4;
 
-  int get length => JS("int", '#(#)', fetchLength, this);
+  int get length => JS("int", '#.length', this);
 
   int operator[](int index) {
     _checkIndex(index, length);
@@ -1048,7 +1036,7 @@
 
   static const int BYTES_PER_ELEMENT = 1;
 
-  int get length => JS("int", '#(#)', fetchLength, this);
+  int get length => JS("int", '#.length', this);
 
   int operator[](int index) {
     _checkIndex(index, length);
@@ -1127,7 +1115,7 @@
 
   static const int BYTES_PER_ELEMENT = 1;
 
-  int get length => JS("int", '#(#)', fetchLength, this);
+  int get length => JS("int", '#.length', this);
 
   int operator[](int index) {
     _checkIndex(index, length);