Don't call dinvoke on Object methods

lib/runtime/dart/collection.js

Index: lib/runtime/dart/collection.js
diff --git a/lib/runtime/dart/collection.js b/lib/runtime/dart/collection.js
index f9be7a825730c28c345d57acd0ecf15deba43e7b..e51de150e9f9517015f3294f6f02157b32c5524e 100644
--- a/lib/runtime/dart/collection.js
+++ b/lib/runtime/dart/collection.js
@@ -24,7 +24,7 @@ var collection;
   }
   // Function _defaultHashCode: (dynamic) → int
   function _defaultHashCode(a) {
-    return dart.as(dart.dload(a, 'hashCode'), core.int);
+    return dart.as(a.hashCode, core.int);
   }
   let HashMap$ = dart.generic(function(K, V) {
     class HashMap extends core.Object {
@@ -3557,7 +3557,7 @@ var collection;
         return dart.notNull(dart.is(key, core.num)) && (key & 0x3ffffff) === key;
       }
       [_computeHashCode](key) {
-        return dart.dload(key, 'hashCode') & 0x3ffffff;
+        return key.hashCode & 0x3ffffff;
       }
       static [_hasTableEntry](table, key) {
         let entry = table[key];
@@ -3965,7 +3965,7 @@ var collection;
         return dart.notNull(dart.is(key, core.num)) && (key & 0x3ffffff) === key;
       }
       [_computeHashCode](key) {
-        return dart.dload(key, 'hashCode') & 0x3ffffff;
+        return key.hashCode & 0x3ffffff;
       }
       static [_getTableEntry](table, key) {
         return table[key];
@@ -4341,7 +4341,7 @@ var collection;
         return dart.notNull(dart.is(element, core.num)) && (element & 0x3ffffff) === element;
       }
       [_computeHashCode](element) {
-        return dart.dload(element, 'hashCode') & 0x3ffffff;
+        return element.hashCode & 0x3ffffff;
       }
       static [_hasTableEntry](table, key) {
         let entry = table[key];
@@ -4713,7 +4713,7 @@ var collection;
         return dart.notNull(dart.is(element, core.num)) && (element & 0x3ffffff) === element;
       }
       [_computeHashCode](element) {
-        return dart.dload(element, 'hashCode') & 0x3ffffff;
+        return element.hashCode & 0x3ffffff;
       }
       static [_getTableEntry](table, key) {
         return table[key];