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 163266)
+++ chrome/browser/nacl_host/nacl_process_host.cc	(working copy)
@@ -656,10 +656,24 @@
 
 #if defined(OS_POSIX)
 SocketDescriptor NaClProcessHost::GetDebugStubSocketHandle() {
-  SocketDescriptor s = net::TCPListenSocket::CreateAndBind("127.0.0.1",
-                                                           kDebugStubPort);
+  NaClBrowser* nacl_browser = NaClBrowser::GetInstance();
+  SocketDescriptor s;
+  if (nacl_browser->HasDebugStubPortListener()) {
+    int port;
+    s = net::TCPListenSocket::CreateAndBindAnyPort("127.0.0.1", &port);
+    if (s != net::TCPListenSocket::kInvalidSocket) {
+      nacl_browser->DebugStubNewPortAllocated(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";
+    close(s);
     return net::TCPListenSocket::kInvalidSocket;
   }
   return s;