Restructure outline shaker tests.

pkg/front_end/test/fasta/shaker_test.dart

 // Copyright (c) 2017, 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.md file.
 
 /// Tests basic functionality of the API tree-shaker.
 ///
 /// Each input file is built and tree-shaken, then we check that the set of
 /// libraries, classes, and members that are retained match those declared in an
 /// expectations file.
 ///
@@ skipping 90 matching lines @@
         platformOutline.unbindCanonicalNames();
         var uriTranslator = await context.options.getUriTranslator();
         var dillTarget = new DillTarget(context.options.ticker, uriTranslator,
             new VmFastaTarget(new TargetFlags(strongMode: false)));
         dillTarget.loader.appendLibraries(platformOutline);
         var sourceTarget = new KernelTarget(
             context.options.fileSystem, false, dillTarget, uriTranslator);
         await dillTarget.buildOutlines();
 
         var inputUri = description.uri;
-        var libUri = inputUri.resolve('lib/lib.dart');
-        sourceTarget.read(libUri);
         sourceTarget.read(inputUri);
         var contents = new File.fromUri(inputUri).readAsStringSync();
         var showCoreLibraries = contents.contains("@@SHOW_CORE_LIBRARIES@@");
         await sourceTarget.buildOutlines();
         var program = await sourceTarget.buildProgram();
-        bool isIncluded(Uri uri) => !_isTreeShaken(uri);
+        bool isIncluded(Uri uri) => uri == inputUri;
         trimProgram(program, isIncluded);
         return pass(
             new _IntermediateData(inputUri, program, showCoreLibraries));
       } on deprecated_InputError catch (e, s) {
         return fail(null, e.error, s);
       }
     });
   }
 }
 
@@ skipping 32 matching lines @@
       return new Result<String>(
           null, context.expectationSet["VerificationError"], errors, null);
     }
 
     // Build a text representation of what we expect to be retained.
     var buffer = new StringBuffer();
     buffer.writeln('DO NOT EDIT -- this file is autogenerated ---');
     buffer.writeln('Tree-shaker preserved the following:');
     for (var library in program.libraries) {
       var importUri = library.importUri;
-      if (!_isTreeShaken(importUri)) continue;
+      if (importUri == entryUri) continue;
       if (importUri.isScheme('dart') && !data.showCoreLibraries) continue;
       String uri = relativizeUri(library.importUri);
       buffer.writeln('\nlibrary $uri:');
       for (var member in library.members) {
         buffer.writeln('  - member ${member.name}');
       }
       for (var typedef_ in library.typedefs) {
         buffer.writeln('  - typedef ${typedef_.name}');
       }
       for (var cls in library.classes) {
@@ skipping 28 matching lines @@
     if (updateExpectations) {
       expectedFile.writeAsStringSync(actualResult);
       return pass(actualResult);
     } else {
       return fail(actualResult, """
 Please create file ${expectedFile.path} with this content:
 $buffer""");
     }
   }
 }
-
-/// A special library used only to test the shaker. The suite above will
-/// tree-shake the contents of this library.
-const _specialLibraryPath = 'pkg/front_end/testcases/shaker/lib/lib.dart';
-
-/// Tree-shake dart:* libraries and the library under [_specialLibraryPath].
-bool _isTreeShaken(Uri uri) =>
-    uri.isScheme('dart') ||
-    Uri.base.resolveUri(uri).path.endsWith(_specialLibraryPath);