Move Tuple to base namespace.

ppapi/proxy/ppapi_proxy_test.cc

Index: ppapi/proxy/ppapi_proxy_test.cc
diff --git a/ppapi/proxy/ppapi_proxy_test.cc b/ppapi/proxy/ppapi_proxy_test.cc
index 949dac39d2eee7c098f46d21a657a8c9d70c470d..64b00e26c6947bc4208b3cf58c075bc0e8aa61a7 100644
--- a/ppapi/proxy/ppapi_proxy_test.cc
+++ b/ppapi/proxy/ppapi_proxy_test.cc
@@ -135,12 +135,13 @@ bool ProxyTestHarnessBase::SupportsInterface(const char* name) {
   if (!reply_msg)
     return false;
 
-  TupleTypes<PpapiMsg_SupportsInterface::ReplyParam>::ValueTuple reply_data;
+  base::TupleTypes<PpapiMsg_SupportsInterface::ReplyParam>::ValueTuple
+      reply_data;
   EXPECT_TRUE(PpapiMsg_SupportsInterface::ReadReplyParam(
       reply_msg, &reply_data));
 
   sink().ClearMessages();
-  return get<0>(reply_data);
+  return base::get<0>(reply_data);
 }
 
 // PluginProxyTestHarness ------------------------------------------------------