dart2js: add --preserve-uris flag.

sdk/lib/_internal/compiler/implementation/dart2js.dart

 // Copyright (c) 2013, 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.cmdline;
 
 import 'dart:async'
     show Future, EventSink;
 import 'dart:io'
     show exit, File, FileMode, Platform, RandomAccessFile, FileSystemException,
@@ skipping 258 matching lines @@
                       (_) => diagnosticHandler.showHints = false),
     new OptionHandler(
         '--output-type=dart|--output-type=dart-multi|--output-type=js',
         setOutputType),
     new OptionHandler('--verbose', setVerbose),
     new OptionHandler('--version', (_) => wantVersion = true),
     new OptionHandler('--library-root=.+', setLibraryRoot),
     new OptionHandler('--out=.+|-o.*', setOutput, multipleArguments: true),
     new OptionHandler('--allow-mock-compilation', passThrough),
     new OptionHandler('--minify|-m', implyCompilation),
+    new OptionHandler('--hide-uris', passThrough),

[Johnni Winther, 2014/09/19 07:54:07]

Should we document this is verbose help?

[floitsch, 2014/09/26 12:51:43]

Done.

     new OptionHandler('--force-strip=.*', setStrip),
     new OptionHandler('--disable-diagnostic-colors',
                       (_) => diagnosticHandler.enableColors = false),
     new OptionHandler('--enable-diagnostic-colors',
                       (_) => diagnosticHandler.enableColors = true),
     new OptionHandler('--enable[_-]checked[_-]mode|--checked',
                       (_) => passThrough('--enable-checked-mode')),
     new OptionHandler('--enable-concrete-type-inference',
                       (_) => implyCompilation(
                           '--enable-concrete-type-inference')),
@@ skipping 358 matching lines @@
       } else {
         print(">>> TEST FAIL");
       }
       stderr.writeln(">>> EOF STDERR");
       runJob();
     });
   }
 
   runJob();
 }