Test that debug stub works with browser.

chrome/browser/nacl_host/nacl_process_host.cc

Index: chrome/browser/nacl_host/nacl_process_host.cc
===================================================================
--- chrome/browser/nacl_host/nacl_process_host.cc	(revision 170891)
+++ chrome/browser/nacl_host/nacl_process_host.cc	(working copy)
@@ -662,10 +662,27 @@
 
 #if defined(OS_POSIX)
 SocketDescriptor NaClProcessHost::GetDebugStubSocketHandle() {
-  SocketDescriptor s = net::TCPListenSocket::CreateAndBind("127.0.0.1",
-                                                           kDebugStubPort);
+  NaClBrowser* nacl_browser = NaClBrowser::GetInstance();
+  SocketDescriptor s;
+  // We allocate currently unused TCP port for debug stub tests. The port
+  // number is passed to the test via debug stub port listener.
+  if (nacl_browser->HasGdbDebugStubPortListener()) {
+    int port;
+    s = net::TCPListenSocket::CreateAndBindAnyPort("127.0.0.1", &port);
+    if (s != net::TCPListenSocket::kInvalidSocket) {
+      nacl_browser->FireGdbDebugStubPortOpened(port);
+    }
+  } else {
+    s = net::TCPListenSocket::CreateAndBind("127.0.0.1", kDebugStubPort);
+  }
+  if (s == net::TCPListenSocket::kInvalidSocket) {
+    LOG(ERROR) << "failed to open socket for debug stub";
+    return net::TCPListenSocket::kInvalidSocket;
+  }
   if (listen(s, 1)) {
     LOG(ERROR) << "listen() failed on debug stub socket";
+    if (HANDLE_EINTR(close(s)) < 0)
+      PLOG(ERROR) << "failed to close debug stub socket";
     return net::TCPListenSocket::kInvalidSocket;
   }
   return s;