Handle use of fromEnvironment from serialized data.

pkg/compiler/lib/src/compiler.dart

Index: pkg/compiler/lib/src/compiler.dart
diff --git a/pkg/compiler/lib/src/compiler.dart b/pkg/compiler/lib/src/compiler.dart
index f44ab1381ba80d6ac927bb008254799cbcadcceb..234c7e17f18c0257c13e2c37efd79c06ba87af7f 100644
--- a/pkg/compiler/lib/src/compiler.dart
+++ b/pkg/compiler/lib/src/compiler.dart
@@ -209,15 +209,6 @@ abstract class Compiler implements LibraryLoaderListener {
   Element loadLibraryFunction;
   Element functionApplyMethod;
 
-  /// The [int.fromEnvironment] constructor.
-  ConstructorElement intEnvironment;
-
-  /// The [bool.fromEnvironment] constructor.
-  ConstructorElement boolEnvironment;
-
-  /// The [String.fromEnvironment] constructor.
-  ConstructorElement stringEnvironment;
-
   // TODO(zarah): Remove this map and incorporate compile-time errors
   // in the model.
   /// Tracks elements with compile-time errors.
@@ -623,12 +614,6 @@ abstract class Compiler implements LibraryLoaderListener {
       mirrorSystemGetNameFunction = cls.lookupLocalMember('getName');
     } else if (mirrorsUsedClass == cls) {
       mirrorsUsedConstructor = cls.constructors.head;
-    } else if (coreClasses.intClass == cls) {
-      intEnvironment = cls.lookupConstructor(Identifiers.fromEnvironment);
-    } else if (coreClasses.stringClass == cls) {
-      stringEnvironment = cls.lookupConstructor(Identifiers.fromEnvironment);
-    } else if (coreClasses.boolClass == cls) {
-      boolEnvironment = cls.lookupConstructor(Identifiers.fromEnvironment);
     }
   }