Fix NaCl plugin shutdown when running the Chrome PPAPI proxy.

webkit/plugins/ppapi/ppapi_plugin_instance.cc

Index: webkit/plugins/ppapi/ppapi_plugin_instance.cc
===================================================================
--- webkit/plugins/ppapi/ppapi_plugin_instance.cc	(revision 150367)
+++ webkit/plugins/ppapi/ppapi_plugin_instance.cc	(working copy)
@@ -402,9 +402,11 @@
   // destroy it. We want to do this prior to calling DidDestroy in case the
   // destructor of the instance object tries to use the instance.
   message_channel_->SetPassthroughObject(NULL);
-  instance_interface_->DidDestroy(pp_instance());
+  // If this is a NaCl plugin instance, allow the trusted NaCl plugin to start
+  // its own shutdown before the untrusted plugin, which may hang.
   if (nacl_plugin_instance_interface_.get())
     nacl_plugin_instance_interface_->DidDestroy(pp_instance());

[dmichael (off chromium), 2012/08/08 22:28:52]

This *should* kill the sel_ldr process where the nacl app is running. Not sure
why it isn't working :-/

+  instance_interface_->DidDestroy(pp_instance());

[bbudge, 2012/08/08 20:31:57]

If this hangs, is there an issue about the code that follows not being run? Or
is hanging not possible?

[dmichael (off chromium), 2012/08/08 22:28:52]

Hmm, it *is* a synchronous message. But if the process is killed while handling
the message, we should get some kind of error?

I don't really understand why the order of these should matter. It seems like
there's a race condition, and somewhere we're not doing the right thing. Did you
ever find out if the audio was repeating on a short interval, or if the plugin
was clearly still producing audio?

 
   if (fullscreen_container_) {
     fullscreen_container_->Destroy();