Revert of Eliminate a potential race in IPC::ChannelProxy (https://codereview.chromium.org/183553004/)

Reason for revert:
Since this has landed, testsuite content_browsertests is failing on bot Android Tests (dbg) on the chromium.linux waterfall.

Specifically, the WebContentsImplBrowserTest.OpenURLSubframe test is consistently crashing, with the following DCHECK:

[FATAL:device_orientation_message_filter.cc(18)] Check failed: BrowserThread::CurrentlyOn(BrowserThread::IO).

This corresponds the the following DCHECK about being on the IO thread:

DeviceOrientationMessageFilter::~DeviceOrientationMessageFilter() {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  if (is_started_)
    DeviceInertialSensorService::GetInstance()->RemoveConsumer(
        CONSUMER_TYPE_ORIENTATION);
}

This same DCHECK failed in one of the try jobs on this CL: http://build.chromium.org/p/tryserver.chromium/builders/android_dbg_triggered_tests/builds/133648

Since this DCHECK has never been observed to fail before (certainly not in the last 200 builds), and has failed both in this CL's try job and twice in a row on the waterfall since landing this CL, it seems very likely that this CL is the cause.

At a guess, the changes to ChannelProxy::Context::OnRemoveFilter seem quite relevant here.

Original issue's description:
> Eliminate a potential race in IPC::ChannelProxy
> 
> Doing the following steps with ChannelProxy leads to a data race:
> 1) Create the ChannelProxy, but don't initialize it.
> 2) Add a filter.
> 3) Init the ChannelProxy.
> 
> The problem is, AddFilter() posts a task from the Listener thread to the IPC task runner to do OnAddFilter. Prior to this patch, OnAddFilter will try to read channel_ even though channel_ may not have been initialized, and it's accessed without any synchronization.
> 
> This patch only really adds the filter if peer_pid_ has been set on the IPC::Channel thread; otherwise, it waits until the connection has been established to really add filters.
> 
> See the bug for more detail.
> 
> BUG=244383
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=256188

TBR=jam@chromium.org,dmichael@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=244383

Review URL: https://codereview.chromium.org/194923004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@256221 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 4 insertions, 17 deletions

diff --git a/ipc/ipc_channel_nacl.cc b/ipc/ipc_channel_nacl.cc
index f796af9..1ecd571 100644
--- a/ipc/ipc_channel_nacl.cc
+++ b/ipc/ipc_channel_nacl.cc
@@ -17,7 +17,6 @@
 #include "base/task_runner_util.h"
 #include "base/threading/simple_thread.h"
 #include "ipc/file_descriptor_set_posix.h"
-#include "ipc/ipc_listener.h"
 #include "ipc/ipc_logging.h"
 #include "native_client/src/public/imc_syscalls.h"
 #include "native_client/src/public/imc_types.h"
@@ -139,15 +138,9 @@ Channel::ChannelImpl::~ChannelImpl() {
   Close();
 }
 
-base::ProcessId Channel::ChannelImpl::peer_pid() const {
-  // This shouldn't actually get used in the untrusted side of the proxy, and we
-  // don't have the real pid anyway.
-  return -1;
-}
-
 bool Channel::ChannelImpl::Connect() {
   if (pipe_ == -1) {
-    DLOG(WARNING) << "Channel creation failed: " << pipe_name_;
+    DLOG(INFO) << "Channel creation failed: " << pipe_name_;
     return false;
   }
 
@@ -171,10 +164,6 @@ bool Channel::ChannelImpl::Connect() {
   waiting_connect_ = false;
   // If there were any messages queued before connection, send them.
   ProcessOutgoingMessages();
-  base::MessageLoopProxy::current()->PostTask(FROM_HERE,
-      base::Bind(&Channel::ChannelImpl::CallOnChannelConnected,
-                 weak_ptr_factory_.GetWeakPtr()));
-
   return true;
 }
 
@@ -304,10 +293,6 @@ bool Channel::ChannelImpl::ProcessOutgoingMessages() {
   return true;
 }
 
-void Channel::ChannelImpl::CallOnChannelConnected() {
-  listener()->OnChannelConnected(peer_pid());
-}
-
 Channel::ChannelImpl::ReadState Channel::ChannelImpl::ReadData(
     char* buffer,
     int buffer_len,
@@ -387,7 +372,9 @@ void Channel::Close() {
 }
 
 base::ProcessId Channel::peer_pid() const {
-  return channel_impl_->peer_pid();
+  // This shouldn't actually get used in the untrusted side of the proxy, and we
+  // don't have the real pid anyway.
+  return -1;
 }
 
 bool Channel::Send(Message* message) {