Add a flag to dump IPC messages sent from the renderer to the browser.

ipc/ipc_channel_proxy.cc

Index: ipc/ipc_channel_proxy.cc
diff --git a/ipc/ipc_channel_proxy.cc b/ipc/ipc_channel_proxy.cc
index 37be200abc7a6ba254961ca23fd676ee580e27d1..901e9b33d206f3ec1518a1dc060838fa5aa101b4 100644
--- a/ipc/ipc_channel_proxy.cc
+++ b/ipc/ipc_channel_proxy.cc
@@ -335,14 +335,15 @@ scoped_ptr<ChannelProxy> ChannelProxy::Create(
 }
 
 ChannelProxy::ChannelProxy(Context* context)
-    : context_(context),
-      did_init_(false) {
+    : context_(context), did_init_(false), outgoing_message_filter_(NULL) {

[inferno, 2015/03/05 18:46:48]

each var on its own line.

[inferno, 2015/03/05 18:46:48]

why not put this var inside ifdef, regular builds don't need this.

 }
 
 ChannelProxy::ChannelProxy(
     Listener* listener,
     const scoped_refptr<base::SingleThreadTaskRunner>& ipc_task_runner)
-    : context_(new Context(listener, ipc_task_runner)), did_init_(false) {
+    : context_(new Context(listener, ipc_task_runner)),
+      did_init_(false),
+      outgoing_message_filter_(NULL) {
 }
 
 ChannelProxy::~ChannelProxy() {
@@ -411,6 +412,9 @@ bool ChannelProxy::Send(Message* message) {
   // TODO(alexeypa): add DCHECK(CalledOnValidThread()) here. Currently there are
   // tests that call Send() from a wrong thread. See http://crbug.com/163523.
 
+  if (outgoing_message_filter())

[inferno, 2015/03/05 18:46:47]

Please add a comment explaining what its purpose is. also, this code behind
ifdef.

+    message = outgoing_message_filter()->Rewrite(message);
+
 #ifdef IPC_MESSAGE_LOG_ENABLED
   Logging::GetInstance()->OnSendMessage(message, context_->channel_id());
 #endif