Less direct Compiler use in SSA

pkg/compiler/lib/src/compiler.dart

 // Copyright (c) 2012, 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.compiler_base;
 
 import 'dart:async' show Future;
 
 import '../compiler_new.dart' as api;
 import 'closure.dart' as closureMapping show ClosureTask;
@@ skipping 277 matching lines @@
     return _codegenWorldBuilder;
   }
 
   bool get analyzeAll => options.analyzeAll || compileAll;
 
   bool get compileAll => false;
 
   bool get disableTypeInference =>
       options.disableTypeInference || compilationFailed;
 
-  // TODO(het): remove this from here. Either inline at all use sites or add it
-  // to Reporter.
-  void unimplemented(Spannable spannable, String methodName) {
-    reporter.internalError(spannable, "$methodName not implemented.");
-  }
-
   // Compiles the dart script at [uri].
   //
   // The resulting future will complete with true if the compilation
   // succeeded.
   Future<bool> run(Uri uri) => selfTask.measureSubtask("Compiler.run", () {
         measurer.startWallClock();
 
         return new Future.sync(() => runInternal(uri))
             .catchError((error) => _reporter.onError(uri, error))
             .whenComplete(() {
@@ skipping 606 matching lines @@
     }
     registerCompileTimeError(currentElement, message);
   }
 
   /**
    * Reads the script specified by the [readableUri].
    *
    * See [LibraryLoader] for terminology on URIs.
    */
   Future<Script> readScript(Uri readableUri, [Spannable node]) {
-    unimplemented(node, 'Compiler.readScript');
-    return null;
+    throw new SpannableAssertionFailure(
+        node, 'Compiler.readScript not implemented.');
   }
 
   Element lookupElementIn(ScopeContainerElement container, String name) {
     Element element = container.localLookup(name);
     if (element == null) {
       throw 'Could not find $name in $container';
     }
     return element;
   }
 
@@ skipping 1046 matching lines @@
   bool isDeferredLoadLibraryGetter(MemberElement member) {
     return member.isDeferredLoaderGetter;
   }
 
   @override
   ResolutionFunctionType getFunctionType(MethodElement method) {
     method.computeType(_resolution);
     return method.type;
   }
 }