PPAPI/NaCl: Make NaClIPCAdapter transfer handles more generally

chrome/nacl/nacl_ipc_adapter.h

Index: chrome/nacl/nacl_ipc_adapter.h
diff --git a/chrome/nacl/nacl_ipc_adapter.h b/chrome/nacl/nacl_ipc_adapter.h
index 7dd0a55c9c79dcada0485f6508f1a4b42599638e..5b323e308efcac37d0710d12abc213725cab0cc8 100644
--- a/chrome/nacl/nacl_ipc_adapter.h
+++ b/chrome/nacl/nacl_ipc_adapter.h
@@ -5,6 +5,7 @@
 #ifndef CHROME_NACL_NACL_IPC_ADAPTER_H_
 #define CHROME_NACL_NACL_IPC_ADAPTER_H_
 
+#include <map>
 #include <queue>
 #include <string>
 
@@ -117,6 +118,12 @@ class NaClIPCAdapter : public base::RefCountedThreadSafe<NaClIPCAdapter>,
     // to be received by the plugin.
     std::queue< scoped_refptr<RewrittenMessage> > to_be_received_;
 
+    // When we send a synchronous message (from untrusted to trusted), we store
+    // its type here, so that later we can associate the reply with its type
+    // and potentially translate handles in the message.
+    typedef std::map<int, uint32> PendingSyncMsgMap;
+    PendingSyncMsgMap pending_sync_msgs_;
+
     // Data that we've queued from the plugin to send, but doesn't consist of a
     // full message yet. The calling code can break apart the message into
     // smaller pieces, and we need to send the message to the other process in