Add moar logging for "Couldn't load plug-in" errors.

ipc/ipc_sync_channel.cc

Index: ipc/ipc_sync_channel.cc
diff --git a/ipc/ipc_sync_channel.cc b/ipc/ipc_sync_channel.cc
index 9a897b534bd333a1c8714794df615964000bb0ca..064de9bd956fc6fa57dc32cc5277e4cfe8bf4c2e 100644
--- a/ipc/ipc_sync_channel.cc
+++ b/ipc/ipc_sync_channel.cc
@@ -302,8 +302,12 @@ bool SyncChannel::SyncContext::TryToUnblockListener(const Message* msg) {
   }
 
   if (!msg->is_reply_error()) {
-    deserializers_.back().send_result = deserializers_.back().deserializer->
+    bool send_result = deserializers_.back().deserializer->
         SerializeOutputParameters(*msg);
+    deserializers_.back().send_result = send_result;
+    LOG_IF(ERROR, !send_result) << "Couldn't deserialize reply message";
+  } else {
+    LOG(ERROR) << "Received error reply";

[piman, 2012/08/10 17:06:15]

I'm afraid this is going to be spammy. There's quite a few places in Chrome
where we return "error" messages under certain legitimate conditions.
If we're going to land this, we should file a bug to remove it.

[Bernhard Bauer, 2012/08/13 07:39:35]

Added a TODO. FWIW, in my (casual) testing this didn't add much more noisiness
to the output that what is already present (we log all Javascript console
messages, for example).

   }
   deserializers_.back().done_event->Signal();
 
@@ -427,6 +431,7 @@ bool SyncChannel::SendWithTimeout(Message* message, int timeout_ms) {
   // *this* might get deleted in WaitForReply.
   scoped_refptr<SyncContext> context(sync_context());
   if (context->shutdown_event()->IsSignaled()) {
+    LOG(ERROR) << "shutdown event is signaled";
     delete message;
     return false;
   }