Prune the old deploy code. This CL does a few changes:

pkg/polymer/lib/component_build.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.
 
 /**
  * Common logic to make it easy to create a `build.dart` for your project.
  *
  * The `build.dart` script is invoked automatically by the Editor whenever a
  * file in the project changes. It must be placed in the root of a project
  * (where pubspec.yaml lives) and should be named exactly 'build.dart'.
@@ skipping 14 matching lines @@
 
 import 'dwc.dart' as dwc;
 import 'src/utils.dart';
 import 'src/compiler_options.dart';
 
 /**
  * Set up 'build.dart' to compile with the dart web components compiler every
  * [entryPoints] listed. On clean commands, the directory where [entryPoints]
  * live will be scanned for generated files to delete them.
  */
-// TODO(jmesserly): we need a better way to automatically detect input files
-Future<List<dwc.CompilerResult>> build(List<String> arguments,
+Future<List<dwc.AnalysisResult>> build(List<String> arguments,
     List<String> entryPoints,
     {bool printTime: true, bool shouldPrint: true}) {
   bool useColors = stdioType(stdout) == StdioType.TERMINAL;
   return asyncTime('Total time', () {
     var args = _processArgs(arguments);
     var tasks = new FutureGroup();
     var lastTask = new Future.value(null);
     tasks.add(lastTask);
 
     var changedFiles = args["changed"];
     var removedFiles = args["removed"];
     var cleanBuild = args["clean"];
     var machineFormat = args["machine"];
     // Also trigger a full build if the script was run from the command line
     // with no arguments
     var fullBuild = args["full"] || (!machineFormat && changedFiles.isEmpty &&
         removedFiles.isEmpty && !cleanBuild);
 
     var options = CompilerOptions.parse(args.rest, checkUsage: false);
 
-    // [outputOnlyDirs] contains directories known to only have output files.
-    // When outputDir is not specified, we create a new directory which only
-    // contains output files. If options.outputDir is specified, we don't know
-    // if the output directory may also have input files. In which case,
-    // [_handleCleanCommand] and [_isInputFile] are more conservative.
-    //
-    // TODO(sigmund): get rid of this. Instead, use the compiler to understand
-    // which files are input or output files.
-    var outputOnlyDirs = options.outputDir == null ? []
-        : entryPoints.map((e) => _outDir(e)).toList();
-
-    if (cleanBuild) {
-      _handleCleanCommand(outputOnlyDirs);
-    } else if (fullBuild
-        || changedFiles.any((f) => _isInputFile(f, outputOnlyDirs))
-        || removedFiles.any((f) => _isInputFile(f, outputOnlyDirs))) {
+    if (fullBuild || !changedFiles.isEmpty || !removedFiles.isEmpty) {
       for (var file in entryPoints) {
         var dwcArgs = new List.from(args.rest);
         if (machineFormat) dwcArgs.add('--json_format');
         if (!useColors) dwcArgs.add('--no-colors');
-        // We'll set 'out/' as the out folder, unless an output directory was
-        // already specified in the command line.
-        if (options.outputDir == null) dwcArgs.addAll(['-o', _outDir(file)]);
         dwcArgs.add(file);
         // Chain tasks to that we run one at a time.
         lastTask = lastTask.then((_) => dwc.run(dwcArgs, printTime: printTime,
             shouldPrint: shouldPrint));
         if (machineFormat) {
           lastTask = lastTask.then((res) {
             appendMessage(Map jsonMessage) {
               var message = json.stringify([jsonMessage]);
               if (shouldPrint) print(message);
               res.messages.add(message);
             }
-            // Print for the Editor messages about mappings and generated files
-            res.outputs.forEach((out, input) {
-              if (out.endsWith(".html") && input != null) {
-                appendMessage({
-                  "method": "mapping",
-                  "params": {"from": input, "to": out},
-                });
-              }
-              appendMessage({"method": "generated", "params": {"file": out}});
-            });
             return res;
           });
         }
         tasks.add(lastTask);
       }
     }
     return tasks.future.then((r) => r.where((v) => v != null));
   }, printTime: printTime, useColors: useColors);
 }
 
-String _outDir(String file) => path.join(path.dirname(file), 'out');
-
-/** Tell whether [filePath] is a generated file. */
-bool _isGeneratedFile(String filePath, List<String> outputOnlyDirs) {
-  var dirPrefix = path.dirname(filePath);
-  for (var outDir in outputOnlyDirs) {
-    if (dirPrefix.startsWith(outDir)) return true;
-  }
-  return path.basename(filePath).startsWith('_');
-}
-
-/** Tell whether [filePath] is an input file. */
-bool _isInputFile(String filePath, List<String> outputOnlyDirs) {
-  var ext = path.extension(filePath);
-  return (ext == '.dart' || ext == '.html') &&
-      !_isGeneratedFile(filePath, outputOnlyDirs);
-}
-
-/**
- * Delete all generated files. Currently we only delete files under directories
- * that are known to contain only generated code.
- */
-void _handleCleanCommand(List<String> outputOnlyDirs) {
-  for (var dirPath in outputOnlyDirs) {
-    var dir = new Directory(dirPath);
-    if (!dir.existsSync()) continue;
-    for (var f in dir.listSync(recursive: false)) {
-      if (f is File && _isGeneratedFile(f.path, outputOnlyDirs)) f.deleteSync();
-    }
-  }
-}
-
 /** Process the command-line arguments. */
 ArgResults _processArgs(List<String> arguments) {
   var parser = new ArgParser()
     ..addOption("changed", help: "the file has changed since the last build",
         allowMultiple: true)
     ..addOption("removed", help: "the file was removed since the last build",
         allowMultiple: true)
     ..addFlag("clean", negatable: false, help: "remove any build artifacts")

[Jennifer Messerly, 2013/08/28 22:25:45]

Consider: adding a note here that we don't actually produce any build artifacts,
so this is a nop

[Siggi Cherem (dart-lang), 2013/08/28 23:17:06]

Done.

     ..addFlag("full", negatable: false, help: "perform a full build")
     ..addFlag("machine", negatable: false,
         help: "produce warnings in a machine parseable format")
     ..addFlag("help", abbr: 'h',
         negatable: false, help: "displays this help and exit");
   var args = parser.parse(arguments);
   if (args["help"]) {
     print('A build script that invokes the web-ui compiler (dwc).');
     print('Usage: dart build.dart [options] [-- [dwc-options]]');
     print('\nThese are valid options expected by build.dart:');
     print(parser.getUsage());
     print('\nThese are valid options expected by dwc:');
     dwc.run(['-h']).then((_) => exit(0));
   }
   return args;
 }