Move Tuple to base namespace.

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 7c4fc0ce7d1b632d4676b314b16609bee01186e2..e4757e5d07fbfca820300fc4a214ac7c380ea9dd 100644
--- a/ppapi/proxy/ppapi_message_utils.h
+++ b/ppapi/proxy/ppapi_message_utils.h
@@ -23,7 +23,7 @@ struct TupleTypeMatch1 {
   static const bool kValue = false;
 };
 template <class A>
-struct TupleTypeMatch1<Tuple<A>, A> {
+struct TupleTypeMatch1<base::Tuple<A>, A> {
   static const bool kValue = true;
 };
 
@@ -32,7 +32,7 @@ struct TupleTypeMatch2 {
   static const bool kValue = false;
 };
 template <class A, class B>
-struct TupleTypeMatch2<Tuple<A, B>, A, B> {
+struct TupleTypeMatch2<base::Tuple<A, B>, A, B> {
   static const bool kValue = true;
 };
 
@@ -41,7 +41,7 @@ struct TupleTypeMatch3 {
   static const bool kValue = false;
 };
 template <class A, class B, class C>
-struct TupleTypeMatch3<Tuple<A, B, C>, A, B, C> {
+struct TupleTypeMatch3<base::Tuple<A, B, C>, A, B, C> {
   static const bool kValue = true;
 };
 
@@ -50,7 +50,7 @@ struct TupleTypeMatch4 {
   static const bool kValue = false;
 };
 template <class A, class B, class C, class D>
-struct TupleTypeMatch4<Tuple<A, B, C, D>, A, B, C, D> {
+struct TupleTypeMatch4<base::Tuple<A, B, C, D>, A, B, C, D> {
   static const bool kValue = true;
 };
 
@@ -59,7 +59,7 @@ struct TupleTypeMatch5 {
   static const bool kValue = false;
 };
 template <class A, class B, class C, class D, class E>
-struct TupleTypeMatch5<Tuple<A, B, C, D, E>, A, B, C, D, E> {
+struct TupleTypeMatch5<base::Tuple<A, B, C, D, E>, A, B, C, D, E> {
   static const bool kValue = true;
 };