Add unit test to check for broker FD leak

sandbox/linux/services/broker_process.h

Index: sandbox/linux/services/broker_process.h
diff --git a/sandbox/linux/services/broker_process.h b/sandbox/linux/services/broker_process.h
index b312b8f67ddaa9e2bd061a39285920b2520e3470..11fd525357fe86ecfb5ac0a05bafbcecc760c512 100644
--- a/sandbox/linux/services/broker_process.h
+++ b/sandbox/linux/services/broker_process.h
@@ -97,6 +97,9 @@ class SANDBOX_EXPORT BrokerProcess {
   const std::vector<std::string> allowed_w_files_;  // Files allowed for write.
   int ipc_socketpair_;  // Our communication channel to parent or child.
   DISALLOW_IMPLICIT_CONSTRUCTORS(BrokerProcess);
+
+  // For test access to ipc_socketpair_.
+  friend void TEST_RecvMsgDescriptorLeak(void*);

[mdempsky, 2014/04/09 23:29:40]

I considered making ipc_socketpair() into a protected method and subclassing
BrokerProcess like you suggested, but I thought this was much more concise and
avoided needing to make BrokerProcess's destructor virtual.

I'm not a fan of having to hard-code the test's macro generated name though (and
I couldn't find any precedent for it in Chromium), but at least it will be
caught at compile-time if things change. :/

 };
 
 }  // namespace sandbox