Revert of ChannelMojo: Ensure that it always has ScopedIPCSupport

content/child/child_thread_impl.cc

Index: content/child/child_thread_impl.cc
diff --git a/content/child/child_thread_impl.cc b/content/child/child_thread_impl.cc
index 685fded9b0544f075196d5d6b3c2448775452f26..013d1d51302d1920edcbe76ec7b463357789c8f5 100644
--- a/content/child/child_thread_impl.cc
+++ b/content/child/child_thread_impl.cc
@@ -56,6 +56,7 @@
 #include "ipc/ipc_sync_channel.h"
 #include "ipc/ipc_sync_message_filter.h"
 #include "ipc/mojo/ipc_channel_mojo.h"
+#include "ipc/mojo/scoped_ipc_support.h"
 
 #if defined(OS_WIN)
 #include "content/common/handle_enumerator_win.h"
@@ -204,6 +205,45 @@
   return ChildThreadImpl::current();
 }
 
+// Mojo client channel delegate to be used in single process mode.
+class ChildThreadImpl::SingleProcessChannelDelegate
+    : public IPC::ChannelMojo::Delegate {
+ public:
+  explicit SingleProcessChannelDelegate(
+      scoped_refptr<base::SequencedTaskRunner> io_runner)
+      : io_runner_(io_runner), weak_factory_(this) {}
+
+  ~SingleProcessChannelDelegate() override {}
+
+  base::WeakPtr<IPC::ChannelMojo::Delegate> ToWeakPtr() override {
+    return weak_factory_.GetWeakPtr();
+  }
+
+  scoped_refptr<base::TaskRunner> GetIOTaskRunner() override {
+    return io_runner_;
+  }
+
+  void OnChannelCreated(base::WeakPtr<IPC::ChannelMojo> channel) override {}
+
+  void DeleteSoon() {
+    io_runner_->PostTask(
+        FROM_HERE,
+        base::Bind(&base::DeletePointer<SingleProcessChannelDelegate>,
+                   base::Unretained(this)));
+  }
+
+ private:
+  scoped_refptr<base::SequencedTaskRunner> io_runner_;
+  base::WeakPtrFactory<IPC::ChannelMojo::Delegate> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(SingleProcessChannelDelegate);
+};
+
+void ChildThreadImpl::SingleProcessChannelDelegateDeleter::operator()(
+    SingleProcessChannelDelegate* delegate) const {
+  delegate->DeleteSoon();
+}
+
 ChildThreadImpl::Options::Options()
     : channel_name(base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
           switches::kProcessChannelID)),
@@ -281,9 +321,15 @@
     VLOG(1) << "Mojo is enabled on child";
     scoped_refptr<base::SequencedTaskRunner> io_task_runner = GetIOTaskRunner();
     DCHECK(io_task_runner);
-    channel_->Init(IPC::ChannelMojo::CreateClientFactory(
-                       nullptr, io_task_runner, channel_name_),
-                   create_pipe_now);
+    if (IsInBrowserProcess())
+      single_process_channel_delegate_.reset(
+          new SingleProcessChannelDelegate(io_task_runner));
+    ipc_support_.reset(new IPC::ScopedIPCSupport(io_task_runner));
+    channel_->Init(
+        IPC::ChannelMojo::CreateClientFactory(
+            single_process_channel_delegate_.get(),
+            channel_name_),
+        create_pipe_now);
     return;
   }