Bug 1402824 - Add missing includes in Scheduler.h to fix non-unified build. r=billm

nsTArray and EventLoopActivation were used without prior declaration.

MozReview-Commit-ID: C05YG6Nzh52

--HG--
extra : rebase_source : 3f78b6a1d73f4d59d3aac4b2da79c27cae404897

xpcom/threads/Scheduler.h

@@ -10,7 +10,9 @@
 #include "mozilla/Attributes.h"
 #include "mozilla/EventQueue.h"
 #include "mozilla/RefPtr.h"
+#include "mozilla/ThreadLocal.h"
 #include "mozilla/UniquePtr.h"
+#include "nsTArray.h"
 
 // Windows silliness. winbase.h defines an empty no-argument Yield macro.
 #undef Yield