Replace base::Tuple implementation with std::tuple

ppapi/proxy/ppapi_message_utils.h

Index: ppapi/proxy/ppapi_message_utils.h
diff --git a/ppapi/proxy/ppapi_message_utils.h b/ppapi/proxy/ppapi_message_utils.h
index fbcb1057ca04590a4df32b7c9e700eff17fd56ab..3fdb51913da34d77087fb02f7fdf772f62a199af 100644
--- a/ppapi/proxy/ppapi_message_utils.h
+++ b/ppapi/proxy/ppapi_message_utils.h
@@ -22,7 +22,7 @@ struct TupleTypeMatch1 {
   static const bool kValue = false;
 };
 template <class A>
-struct TupleTypeMatch1<base::Tuple<A>, A> {
+struct TupleTypeMatch1<std::tuple<A>, A> {
   static const bool kValue = true;
 };
 
@@ -31,7 +31,7 @@ struct TupleTypeMatch2 {
   static const bool kValue = false;
 };
 template <class A, class B>
-struct TupleTypeMatch2<base::Tuple<A, B>, A, B> {
+struct TupleTypeMatch2<std::tuple<A, B>, A, B> {
   static const bool kValue = true;
 };
 
@@ -40,7 +40,7 @@ struct TupleTypeMatch3 {
   static const bool kValue = false;
 };
 template <class A, class B, class C>
-struct TupleTypeMatch3<base::Tuple<A, B, C>, A, B, C> {
+struct TupleTypeMatch3<std::tuple<A, B, C>, A, B, C> {
   static const bool kValue = true;
 };
 
@@ -49,7 +49,7 @@ struct TupleTypeMatch4 {
   static const bool kValue = false;
 };
 template <class A, class B, class C, class D>
-struct TupleTypeMatch4<base::Tuple<A, B, C, D>, A, B, C, D> {
+struct TupleTypeMatch4<std::tuple<A, B, C, D>, A, B, C, D> {
   static const bool kValue = true;
 };
 
@@ -58,7 +58,7 @@ struct TupleTypeMatch5 {
   static const bool kValue = false;
 };
 template <class A, class B, class C, class D, class E>
-struct TupleTypeMatch5<base::Tuple<A, B, C, D, E>, A, B, C, D, E> {
+struct TupleTypeMatch5<std::tuple<A, B, C, D, E>, A, B, C, D, E> {
   static const bool kValue = true;
 };