No longer store the compilation-context in WorkItem.

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

Index: pkg/compiler/lib/src/ssa/interceptor_simplifier.dart
diff --git a/pkg/compiler/lib/src/ssa/interceptor_simplifier.dart b/pkg/compiler/lib/src/ssa/interceptor_simplifier.dart
index 8cc746748cdbbae1aba411a580985f6a7cdea446..a12a57efe1f1f40e9ed5aecfe7977ad9dd4ebd1e 100644
--- a/pkg/compiler/lib/src/ssa/interceptor_simplifier.dart
+++ b/pkg/compiler/lib/src/ssa/interceptor_simplifier.dart
@@ -40,10 +40,10 @@ class SsaSimplifyInterceptors extends HBaseVisitor
   final String name = "SsaSimplifyInterceptors";
   final ConstantSystem constantSystem;
   final Compiler compiler;
-  final CodegenWorkItem work;
+  final Element element;
   HGraph graph;
 
-  SsaSimplifyInterceptors(this.compiler, this.constantSystem, this.work);
+  SsaSimplifyInterceptors(this.compiler, this.constantSystem, this.element);
 
   JavaScriptBackend get backend => compiler.backend;
 
@@ -129,7 +129,7 @@ class SsaSimplifyInterceptors extends HBaseVisitor
 
     // If we just happen to be in an instance method of the constant
     // interceptor, `this` is a shorter alias.
-    if (constantInterceptor == work.element.enclosingClass &&
+    if (constantInterceptor == element.enclosingClass &&
         graph.thisInstruction != null) {
       return graph.thisInstruction;
     }