[mojo-edk] Cache the context thread-local in the RequestContext.

mojo/edk/system/request_context.h

Index: mojo/edk/system/request_context.h
diff --git a/mojo/edk/system/request_context.h b/mojo/edk/system/request_context.h
index 75ba61fdf6cccc2128122d368928f3be5c3a1518..56b849870e33ba07048d5f450e911880be51b045 100644
--- a/mojo/edk/system/request_context.h
+++ b/mojo/edk/system/request_context.h
@@ -10,6 +10,10 @@
 #include "mojo/edk/system/handle_signals_state.h"
 #include "mojo/edk/system/watcher.h"
 
+namespace base {
+template<typename T> class ThreadLocalPointer;
+}
+
 namespace mojo {
 namespace edk {
 
@@ -73,6 +77,11 @@ class RequestContext {
   WatchNotifyFinalizerList watch_notify_finalizers_;
   WatchCancelFinalizerList watch_cancel_finalizers_;
 
+  // Pointer to the TLS context. Although this can easily be accessed via the
+  // global LazyInstance, accessing a LazyInstance has a large cost relative to
+  // the rest of this class and its usages.
+  base::ThreadLocalPointer<RequestContext>* tls_context_;

[Ken Rockot(use gerrit already), 2016/03/07 04:25:00]

Hmm, couldn't this just be a raw pointer?

+
   DISALLOW_COPY_AND_ASSIGN(RequestContext);
 };