Add support for compiling Dart via the FE in dart2js.

pkg/compiler/lib/src/js_backend/backend_impact.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library dart2js.js_helpers.impact;
 
 import '../common/names.dart';
 import '../common_elements.dart' show CommonElements, ElementEnvironment;
 import '../elements/types.dart' show InterfaceType;
 import '../elements/entities.dart';
@@ skipping 185 matching lines @@
 
   BackendImpact get asCheck {
     return _asCheck ??=
         new BackendImpact(staticUses: [_commonElements.throwRuntimeError]);
   }
 
   BackendImpact _throwNoSuchMethod;
 
   BackendImpact get throwNoSuchMethod {
     return _throwNoSuchMethod ??= new BackendImpact(
-        instantiatedClasses: _options.useKernel
+        instantiatedClasses: _options.useKernelInSsa
             ? [
                 _commonElements.symbolImplementationClass,
               ]
             : [],
-        staticUses: _options.useKernel
+        staticUses: _options.useKernelInSsa
             ? [
                 _commonElements.genericNoSuchMethod,
                 _commonElements.unresolvedConstructorError,
                 _commonElements.unresolvedStaticMethodError,
                 _commonElements.unresolvedStaticGetterError,
                 _commonElements.unresolvedStaticSetterError,
                 _commonElements.unresolvedTopLevelMethodError,
                 _commonElements.unresolvedTopLevelGetterError,
                 _commonElements.unresolvedTopLevelSetterError,
                 _commonElements.symbolConstructorTarget,
@@ skipping 58 matching lines @@
       _commonElements.jsFixedArrayClass,
       _commonElements.jsExtendableArrayClass,
       _commonElements.jsUnmodifiableArrayClass
     ]);
   }
 
   BackendImpact _throwRuntimeError;
 
   BackendImpact get throwRuntimeError {
     return _throwRuntimeError ??= new BackendImpact(
-        staticUses: _options.useKernel
+        staticUses: _options.useKernelInSsa
             ? [
                 // TODO(sra): Refactor impacts so that we know which of these
                 // are called.
                 _commonElements.malformedTypeError,
                 _commonElements.throwRuntimeError,
               ]
             : [
                 _commonElements.throwRuntimeError,
               ],
         otherImpacts: [
@@ skipping 197 matching lines @@
 
   BackendImpact get checkedModeTypeCheck {
     return _checkedModeTypeCheck ??=
         new BackendImpact(staticUses: [_commonElements.throwRuntimeError]);
   }
 
   BackendImpact _malformedTypeCheck;
 
   BackendImpact get malformedTypeCheck {
     return _malformedTypeCheck ??= new BackendImpact(
-        staticUses: _options.useKernel
+        staticUses: _options.useKernelInSsa
             ? [
                 _commonElements.malformedTypeError,
               ]
             : [
                 _commonElements.throwTypeError,
               ]);
   }
 
   BackendImpact _genericTypeCheck;
 
@@ skipping 284 matching lines @@
   /// Backend impact for type variables through mirrors.
   BackendImpact get typeVariableMirror {
     return _typeVariableMirror ??= new BackendImpact(staticUses: [
       _commonElements.typeVariableConstructor,
       _commonElements.createRuntimeType
     ], instantiatedClasses: [
       _commonElements.typeVariableClass
     ]);
   }
 }