patch from petermayo to fix GN dependency regeneration

tools/gn/scheduler.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "tools/gn/scheduler.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/strings/string_number_conversions.h"
 #include "tools/gn/standard_out.h"
@@ skipping 95 matching lines @@
 std::vector<base::FilePath> Scheduler::GetGenDependencies() const {
   base::AutoLock lock(lock_);
   return gen_dependencies_;
 }
 
 void Scheduler::AddWrittenFile(const SourceFile& file) {
   base::AutoLock lock(lock_);
   written_files_.push_back(file);
 }
 
+std::vector<SourceFile> Scheduler::GetWrittenFiles() const {
+  base::AutoLock lock(lock_);
+  return written_files_;
+}
+
 void Scheduler::AddUnknownGeneratedInput(const Target* target,
                                          const SourceFile& file) {
   base::AutoLock lock(lock_);
   unknown_generated_inputs_.insert(std::make_pair(file, target));
 }
 
 std::multimap<SourceFile, const Target*>
     Scheduler::GetUnknownGeneratedInputs() const {
   base::AutoLock lock(lock_);
 
@@ skipping 45 matching lines @@
 void Scheduler::DoWork(const base::Closure& closure) {
   closure.Run();
   DecrementWorkCount();
 }
 
 void Scheduler::OnComplete() {
   // Should be called on the main thread.
   DCHECK(base::MessageLoop::current() == main_loop());
   runner_.Quit();
 }