Update mojo sdk to rev f6c8ec07c01deebc13178d516225fd12695c3dc2

mojo/public/cpp/utility/lib/run_loop.cc

Index: mojo/public/cpp/utility/lib/run_loop.cc
diff --git a/mojo/public/cpp/utility/lib/run_loop.cc b/mojo/public/cpp/utility/lib/run_loop.cc
index 9707e7ecf76600bfd3b99637f654e1a9b2625c7a..432365f3d4cec9f76abb4759bb8a9129a0096757 100644
--- a/mojo/public/cpp/utility/lib/run_loop.cc
+++ b/mojo/public/cpp/utility/lib/run_loop.cc
@@ -37,7 +37,7 @@ struct RunLoop::RunState {
 };
 
 RunLoop::RunLoop()
-    : run_state_(NULL), next_handler_id_(0), next_sequence_number_(0) {
+    : run_state_(nullptr), next_handler_id_(0), next_sequence_number_(0) {
   assert(!current());
   current_run_loop.Set(this);
 }
@@ -45,7 +45,7 @@ RunLoop::RunLoop()
 RunLoop::~RunLoop() {
   assert(current() == this);
   NotifyHandlers(MOJO_RESULT_ABORTED, IGNORE_DEADLINE);
-  current_run_loop.Set(NULL);
+  current_run_loop.Set(nullptr);
 }
 
 // static