Lesser direct Compiler use in SSA

pkg/compiler/lib/src/ssa/builder_kernel.dart

 // Copyright (c) 2016, 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.
 
 import 'package:kernel/ast.dart' as ir;
 
 import '../closure.dart';
 import '../common.dart';
 import '../common/codegen.dart' show CodegenRegistry, CodegenWorkItem;
 import '../common/names.dart';
@@ skipping 97 matching lines @@
   /// factory constructors.  These types are preserved in [HInvokeStatic]s and
   /// [HCreate]s inside the inline code and registered during code generation
   /// for these nodes.
   // TODO(karlklose): consider removing this and keeping the (substituted) types
   // of the type variables in an environment (like the [LocalsHandler]).
   final List<ResolutionDartType> currentImplicitInstantiations =
       <ResolutionDartType>[];
 
   HInstruction rethrowableException;
 
+  final Compiler compiler;
+
   @override
   JavaScriptBackend get backend => compiler.backend;
 
   @override
   TreeElements get elements => astAdapter.elements;
 
   SourceInformationBuilder sourceInformationBuilder;
   KernelAstAdapter astAdapter;
   LoopHandler<ir.Node> loopHandler;
   TypeBuilder typeBuilder;
 
   final Map<ir.VariableDeclaration, HInstruction> letBindings =
       <ir.VariableDeclaration, HInstruction>{};
 
   /// True if we are visiting the expression of a throw statement; we assume
   /// this is a slow path.
   bool _inExpressionOfThrow = false;
 
   KernelSsaBuilder(
       this.targetElement,
       this.resolvedAst,
-      Compiler compiler,
+      this.compiler,
       this.closedWorld,
       this.registry,
       SourceInformationStrategy sourceInformationFactory,
       Kernel kernel) {
-    this.compiler = compiler;
     this.loopHandler = new KernelLoopHandler(this);
     typeBuilder = new TypeBuilder(this);
     graph.element = targetElement;
     // TODO(het): Should sourceInformationBuilder be in GraphBuilder?
     this.sourceInformationBuilder =
         sourceInformationFactory.createBuilderForContext(resolvedAst);
     graph.sourceInformation =
         sourceInformationBuilder.buildVariableDeclaration();
     this.localsHandler = new LocalsHandler(
         this, targetElement, null, nativeData, interceptorData);
@@ skipping 3069 matching lines @@
     enterBlock.setBlockFlow(
         new HTryBlockInformation(
             kernelBuilder.wrapStatementGraph(bodyGraph),
             exception,
             kernelBuilder.wrapStatementGraph(catchGraph),
             kernelBuilder.wrapStatementGraph(finallyGraph)),
         exitBlock);
     kernelBuilder.inTryStatement = previouslyInTryStatement;
   }
 }