Mac: Proof of concept of IPCing renderer mach_port_ts.

chrome/common/mach_ipc_mac.h

Index: chrome/common/mach_ipc_mac.h
diff --git a/chrome/common/mach_ipc_mac.h b/chrome/common/mach_ipc_mac.h
index 8c345ddfda72a759b29878378861e1af51a3214a..47f767a8e13f1533417553c7c51cebd1acf53545 100644
--- a/chrome/common/mach_ipc_mac.h
+++ b/chrome/common/mach_ipc_mac.h
@@ -167,8 +167,9 @@ class MachMessage {
   bool AddDescriptor(const MachMsgPortDescriptor &desc);
 
   int GetDescriptorCount() const {
-                                   return storage_->body.msgh_descriptor_count;
-                                 }
+    return storage_->body.msgh_descriptor_count;
+  }
+
   MachMsgPortDescriptor *GetDescriptor(int n);
 
   // Convenience method which gets the mach port described by the descriptor
@@ -284,7 +285,7 @@ class ReceivePort {
 
   // Waits on the mach port until message received or timeout
   kern_return_t WaitForMessage(MachReceiveMessage *out_message,
-                               mach_msg_timeout_t timeout);
+                               mach_msg_timeout_t timeout);  // in milliseconds
 
   // The underlying mach port that we wrap
   mach_port_t  GetPort() const { return port_; }