Move patch file generation to fasta.

pkg/front_end/lib/src/fasta/compile_platform.dart

 // Copyright (c) 2016, 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 fasta.compile_platform;
 
 import 'dart:async' show Future;
 
 import 'ticker.dart' show Ticker;
 
@@ skipping 11 matching lines @@
 
 import 'translate_uri.dart' show TranslateUri;
 
 const int iterations = const int.fromEnvironment("iterations", defaultValue: 1);
 
 Future mainEntryPoint(List<String> arguments) async {
   for (int i = 0; i < iterations; i++) {
     if (i > 0) {
       print("\n");
     }
-    Ticker ticker = new Ticker();
     try {
-      await CompilerCommandLine.withGlobalOptions("compile_platform", arguments,
-          (CompilerContext c) => compilePlatform(c, ticker));
+      await compilePlatform(arguments);
     } on InputError catch (e) {
       exitCode = 1;
       print(e.format());
       return null;
     }
   }
 }
 
-Future compilePlatform(CompilerContext c, Ticker ticker) async {
+Future compilePlatform(List<String> arguments) async {
+  Ticker ticker = new Ticker();
+  await CompilerCommandLine.withGlobalOptions("compile_platform", arguments,
+      (CompilerContext c) {
+    Uri patchedSdk = Uri.base.resolveUri(new Uri.file(c.options.arguments[0]));
+    Uri output = Uri.base.resolveUri(new Uri.file(c.options.arguments[1]));
+    return compilePlatformInternal(c, ticker, patchedSdk, output);
+  });
+}
+
+Future compilePlatformInternal(
+    CompilerContext c, Ticker ticker, Uri patchedSdk, Uri output) async {
   ticker.isVerbose = c.options.verbose;
-  Uri output = Uri.base.resolveUri(new Uri.file(c.options.arguments[1]));
-  Uri deps = Uri.base.resolveUri(new Uri.file("${c.options.arguments[1]}.d"));
-  Uri patchedSdk = Uri.base.resolveUri(new Uri.file(c.options.arguments[0]));
+  Uri deps = Uri.base.resolveUri(new Uri.file("${output.toFilePath()}.d"));
   ticker.logMs("Parsed arguments");
   if (ticker.isVerbose) {
     print("Compiling $patchedSdk to $output");
   }
 
   TranslateUri uriTranslator =
       await TranslateUri.parse(patchedSdk, c.options.packages);
   ticker.logMs("Read packages file");
 
   DillTarget dillTarget = new DillTarget(ticker, uriTranslator);
   KernelTarget kernelTarget =
       new KernelTarget(dillTarget, uriTranslator, c.uriToSource);
 
   kernelTarget.read(Uri.parse("dart:core"));
   await dillTarget.writeOutline(null);
   await kernelTarget.writeOutline(output);
 
   if (exitCode != 0) return null;
   await kernelTarget.writeProgram(output,
       dumpIr: c.options.dumpIr, verify: c.options.verify);
   await kernelTarget.writeDepsFile(output, deps);
 }