GN threading refactor

tools/gn/scheduler.cc

Index: tools/gn/scheduler.cc
diff --git a/tools/gn/scheduler.cc b/tools/gn/scheduler.cc
index 72c310bb071d1072698e3bdee6cf18b56c793965..254de0d5a097d6a4b5e24e8b7898de09cae33ce8 100644
--- a/tools/gn/scheduler.cc
+++ b/tools/gn/scheduler.cc
@@ -7,7 +7,6 @@
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/strings/string_number_conversions.h"
-#include "tools/gn/ninja_target_writer.h"
 #include "tools/gn/standard_out.h"
 
 Scheduler* g_scheduler = NULL;
@@ -31,17 +30,22 @@ Scheduler::Scheduler()
       input_file_manager_(new InputFileManager),
       verbose_logging_(false),
       work_count_(0),
-      is_failed_(false) {
+      is_failed_(false),
+      has_been_shutdown_(false) {
   g_scheduler = this;
 }
 
 Scheduler::~Scheduler() {
+  if (!has_been_shutdown_)
+    pool_->Shutdown();
   g_scheduler = NULL;
 }
 
 bool Scheduler::Run() {
   runner_.Run();
+  base::AutoLock lock(lock_);
   pool_->Shutdown();
+  has_been_shutdown_ = true;
   return !is_failed();
 }
 
@@ -86,13 +90,6 @@ void Scheduler::ScheduleWork(const base::Closure& work) {
       base::SequencedWorkerPool::BLOCK_SHUTDOWN);
 }
 
-void Scheduler::ScheduleTargetFileWrite(const Target* target) {
-  pool_->PostWorkerTaskWithShutdownBehavior(
-      FROM_HERE, base::Bind(&Scheduler::DoTargetFileWrite,
-                            base::Unretained(this), target),
-      base::SequencedWorkerPool::BLOCK_SHUTDOWN);
-}
-
 void Scheduler::AddGenDependency(const base::FilePath& file) {
   base::AutoLock lock(lock_);
   gen_dependencies_.push_back(file);
@@ -130,10 +127,6 @@ void Scheduler::FailWithErrorOnMainThread(const Err& err) {
   runner_.Quit();
 }
 
-void Scheduler::DoTargetFileWrite(const Target* target) {
-  NinjaTargetWriter::RunAndWriteFile(target);
-}
-
 void Scheduler::DoWork(const base::Closure& closure) {
   closure.Run();
   DecrementWorkCount();