Add a vmservice_sdk directory in runtime/bin.

tools/patch_sdk.dart

 #!/usr/bin/env dart
 // Copyright (c) 2015, 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.
 
 /// Command line tool to merge the SDK libraries and our patch files.
 /// This is currently designed as an offline tool, but we could automate it.
 
 import 'dart:io';
 import 'dart:isolate' show RawReceivePort;
@@ skipping 101 matching lines @@
   Uri vmserviceIo = outDirUri.resolve('vmservice_io.dill');
   Uri librariesJson = outDirUri.resolve("lib/libraries.json");
   Uri packages = Uri.base.resolveUri(new Uri.file(packagesFile));
 
   await _writeSync(
       librariesJson.toFilePath(), JSON.encode({"libraries": locations}));
 
   if (forVm) {
     await fasta.compilePlatform(outDirUri, platform,
         packages: packages, outlineOutput: outline);
+    var base = path.fromUri(Platform.script);
+    Uri sdkDir =

[Siggi Cherem (dart-lang), 2017/06/15 01:10:19]

nit: rename to `repositoryDir`? `sdkDir` might be confused with the many other
sdk dirs we have (patched_sdk, vmservice_sdk).

[sivachandra, 2017/06/15 06:10:54]

Done.

+        new Uri.directory(path.dirname(path.dirname(path.absolute(base))));
+    Uri vmserviceSdk = sdkDir.resolve('runtime/bin/vmservice_sdk/');

[Siggi Cherem (dart-lang), 2017/06/15 01:10:19]

I'd like to eventually get rid of the fake vmservice_sdk folder. I believe you
need this because fasta doesn't have a flag to provide the libraries.json
directly, but you need to provide a --sdk flag instead.

For now, I'm ok adding a TODO referring to
https://github.com/dart-lang/sdk/issues/29882. 

Eventually the fix might be to add that flag so you can use libraries.json
directly next to vmservice_io.dart, or, we can use a different API here and
provide the contents of libraries.json in memory instead. For example, instead
of calling fasta.compile, you would invoke the public API in
package:front_end/kernel_generator.dart. That public API has an option to
specify the dartLibraries
(https://github.com/dart-lang/sdk/blob/master/pkg/front_end/lib/compiler_optio...)
explicitly.

I prefer the latter approach and had the intention of anyways migrating this
entire file to use the public APIs in the near future. I'm happy to switch this
call here together with the rest.

[sivachandra, 2017/06/15 06:10:54]

Added the TODO.

     await fasta.compile([

[Siggi Cherem (dart-lang), 2017/06/15 01:10:19]

now that this is independent of building the patched_sdk, I wonder if we should
pull this out of the patch_sdk.dart script entirely, and instead use a separate
build rule to generate the vmservice.dill file. WDYT?

[sivachandra, 2017/06/15 06:10:54]

I considered that approach but decided against it because of:

1. We want to co-locate platform.dill and vmservice_io.dill in a single
directory to avoid multiple options to the VM. See
https://codereview.chromium.org/2933203004/
2. Dealing with *.dill files directly is only a temporary measure. We want to
move over to snapshots as soon as possible (which might be a few weeks away).

-      "--sdk=${outDirUri.toString()}",
+      "--sdk=${vmserviceSdk.toString()}",

[Siggi Cherem (dart-lang), 2017/06/15 01:10:19]

FYI - I happen to just land a CL that updates these lines slightly, so you may
have a conflict here.

Note also that you can simply write '$vmserviceSdk' here. The .toString is
implicitly called when using interpolation. I also prefer writing '$foo' instead
of foo.toString() (e.g. like the in the last argument below)

[sivachandra, 2017/06/15 06:10:54]

Done.

       "--platform=${outline.toString()}",
       "--packages=${packages.toString()}",
       "dart:vmservice_io",
       "-o",
       vmserviceIo.toString()
     ]);
   } else {
     await dart2js.compilePlatform(outDirUri, platform,
         packages: packages, outlineOutput: outline);
   }
@@ skipping 62 matching lines @@
   ]) {
     var vmLibrary = tuple[0];
     var dartFile = tuple[1];
 
     // The "dart:_builtin" library is only available for the DartVM.
     var builtinLibraryIn = path.join(dartDir, 'runtime', 'bin', dartFile);
     var builtinLibraryOut = path.join(sdkOut, vmLibrary, '${vmLibrary}.dart');
     _writeSync(builtinLibraryOut, readInputFile(builtinLibraryIn));
     locations[vmLibrary] = path.join(vmLibrary, '${vmLibrary}.dart');
   }
-
-  for (var file in ['loader.dart', 'server.dart', 'vmservice_io.dart']) {
-    var libraryIn = path.join(dartDir, 'runtime', 'bin', 'vmservice', file);
-    var libraryOut = path.join(sdkOut, 'vmservice_io', file);
-    _writeSync(libraryOut, readInputFile(libraryIn));
-  }
-  locations["vmservice_io"] = "vmservice_io/vmservice_io.dart";
-  locations["_vmservice"] = "vmservice/vmservice.dart";
 }
 
 _applyPatch(SdkLibrary library, String sdkLibIn, String patchIn, String sdkOut,
     Map<String, String> locations) {
   var libraryOut = path.join(sdkLibIn, library.path);
   var libraryIn = libraryOut;
 
   var libraryFile = getInputFile(libraryIn, canBeMissing: true);
   if (libraryFile != null) {
     locations[Uri.parse(library.shortName).path] =
@@ skipping 395 matching lines @@
     if (diff != 0) return diff;
     return end - other.end;
   }
 }
 
 List<SdkLibrary> _getSdkLibraries(String contents, bool useDart2js) {
   var libraryBuilder = new SdkLibrariesReader_LibraryBuilder(useDart2js);
   parseCompilationUnit(contents).accept(libraryBuilder);
   return libraryBuilder.librariesMap.sdkLibraries;
 }