Revert 260373 "Add a temporary CHECK to IPC::Channel::Send() to ..."

> Add a temporary CHECK to IPC::Channel::Send() to help track down crash.
> 
> TBR=cbentzel@chromium.org, cpu@chromium.org
> BUG=357915
> 
> Review URL: https://codereview.chromium.org/216293008

TBR=viettrungluu@chromium.org

Review URL: https://codereview.chromium.org/217323004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@260393 0039d316-1c4b-4281-b951-d872f2087c98

ipc/ipc_channel_posix.cc

@@ -527,7 +527,6 @@ bool Channel::ChannelImpl::ProcessOutgoingMessages() {
 }
 
 bool Channel::ChannelImpl::Send(Message* message) {
-  CHECK(message) << "crbug.com/357915";  // TODO(vtl): Remove once bug resolved.
   DVLOG(2) << "sending message @" << message << " on channel @" << this
            << " with type " << message->type()
            << " (" << output_queue_.size() << " in queue)";

ipc/ipc_channel_win.cc

@@ -81,7 +81,6 @@ void Channel::ChannelImpl::Close() {
 }
 
 bool Channel::ChannelImpl::Send(Message* message) {
-  CHECK(message) << "crbug.com/357915";  // TODO(vtl): Remove once bug resolved.
   DCHECK(thread_check_->CalledOnValidThread());
   DVLOG(2) << "sending message @" << message << " on channel @" << this
            << " with type " << message->type()