Update mojo sdk to rev afb4440fd5a10cba980878c326180b7ad7960480

mojo/edk/system/channel_info.cc

Index: mojo/edk/system/channel_info.cc
diff --git a/mojo/edk/system/channel_info.cc b/mojo/edk/system/channel_info.cc
index efc5f0409161f51466b3189a9817e936ca936f6f..6d23215e905f1d60decf281a8644431ed22aeaec 100644
--- a/mojo/edk/system/channel_info.cc
+++ b/mojo/edk/system/channel_info.cc
@@ -4,6 +4,8 @@
 
 #include "mojo/edk/system/channel_info.h"
 
+#include <algorithm>
+
 namespace mojo {
 namespace system {
 
@@ -19,5 +21,11 @@ ChannelInfo::ChannelInfo(
 ChannelInfo::~ChannelInfo() {
 }
 
+void ChannelInfo::Swap(ChannelInfo* other) {
+  // Note: Swapping avoids refcount churn.
+  std::swap(channel, other->channel);
+  std::swap(channel_thread_task_runner, other->channel_thread_task_runner);
+}
+
 }  // namespace system
 }  // namespace mojo