Reland "Add enable_ipc_logging build argument"

content/child/child_thread_impl.cc

Index: content/child/child_thread_impl.cc
diff --git a/content/child/child_thread_impl.cc b/content/child/child_thread_impl.cc
index f91f11f74e38def29aed7e45a9dae7bb2297e870..a3a73543115d76216f5969fc4b0a78def95f6a0b 100644
--- a/content/child/child_thread_impl.cc
+++ b/content/child/child_thread_impl.cc
@@ -414,7 +414,7 @@ void ChildThreadImpl::Init(const Options& options) {
   g_lazy_tls.Pointer()->Set(this);
   on_channel_error_called_ = false;
   message_loop_ = base::MessageLoop::current();
-#ifdef IPC_MESSAGE_LOG_ENABLED
+#if BUILDFLAG(IPC_MESSAGE_LOG_ENABLED)
   // We must make sure to instantiate the IPC Logger *before* we create the
   // channel, otherwise we can get a callback on the IO thread which creates
   // the logger, and the logger does not like being created on the IO thread.
@@ -424,7 +424,7 @@ void ChildThreadImpl::Init(const Options& options) {
   channel_ =
       IPC::SyncChannel::Create(this, ChildProcess::current()->io_task_runner(),
                                ChildProcess::current()->GetShutDownEvent());
-#ifdef IPC_MESSAGE_LOG_ENABLED
+#if BUILDFLAG(IPC_MESSAGE_LOG_ENABLED)
   if (!IsInBrowserProcess())
     IPC::Logging::GetInstance()->SetIPCSender(this);
 #endif
@@ -570,7 +570,7 @@ void ChildThreadImpl::Init(const Options& options) {
 }
 
 ChildThreadImpl::~ChildThreadImpl() {
-#ifdef IPC_MESSAGE_LOG_ENABLED
+#if BUILDFLAG(IPC_MESSAGE_LOG_ENABLED)
   IPC::Logging::GetInstance()->SetIPCSender(NULL);
 #endif
 
@@ -720,7 +720,7 @@ bool ChildThreadImpl::OnMessageReceived(const IPC::Message& msg) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(ChildThreadImpl, msg)
     IPC_MESSAGE_HANDLER(ChildProcessMsg_Shutdown, OnShutdown)
-#if defined(IPC_MESSAGE_LOG_ENABLED)
+#if BUILDFLAG(IPC_MESSAGE_LOG_ENABLED)
     IPC_MESSAGE_HANDLER(ChildProcessMsg_SetIPCLoggingEnabled,
                         OnSetIPCLoggingEnabled)
 #endif
@@ -791,7 +791,7 @@ void ChildThreadImpl::OnShutdown() {
   base::MessageLoop::current()->QuitWhenIdle();
 }
 
-#if defined(IPC_MESSAGE_LOG_ENABLED)
+#if BUILDFLAG(IPC_MESSAGE_LOG_ENABLED)
 void ChildThreadImpl::OnSetIPCLoggingEnabled(bool enable) {
   if (enable)
     IPC::Logging::GetInstance()->Enable();