Bug 1402824 - Include nsTArray.h in InputEventStatistics.h to fix non-unified build. r=smaug

The nsTArray type was used without prior declaration.

MozReview-Commit-ID: KMUgXO2kBIY

--HG--
extra : rebase_source : 3bdca144a43ef7353ef9a62f94dfdc6dc2adfcc0

xpcom/threads/InputEventStatistics.h

@@ -11,6 +11,7 @@
 #include "mozilla/Maybe.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/TimeStamp.h"
+#include "nsTArray.h"
 
 namespace mozilla {