Revert of Move content's shell connections to the IO thread

content/renderer/mus/render_widget_window_tree_client_factory.cc

Index: content/renderer/mus/render_widget_window_tree_client_factory.cc
diff --git a/content/renderer/mus/render_widget_window_tree_client_factory.cc b/content/renderer/mus/render_widget_window_tree_client_factory.cc
index a068781875828229fc483370ca6d8b752d7e54a7..ef56edd1be5ddd10bc8fa4a5665ac2064db50596 100644
--- a/content/renderer/mus/render_widget_window_tree_client_factory.cc
+++ b/content/renderer/mus/render_widget_window_tree_client_factory.cc
@@ -9,14 +9,11 @@
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
-#include "base/memory/ref_counted.h"
-#include "base/sequenced_task_runner.h"
-#include "base/threading/thread_task_runner_handle.h"
 #include "content/common/render_widget_window_tree_client_factory.mojom.h"
-#include "content/public/common/connection_filter.h"
 #include "content/public/common/mojo_shell_connection.h"
 #include "content/renderer/mus/render_widget_mus_connection.h"
 #include "mojo/public/cpp/bindings/binding_set.h"
+#include "services/shell/public/cpp/connection.h"
 #include "services/shell/public/cpp/interface_factory.h"
 #include "services/shell/public/cpp/service.h"
 #include "services/ui/public/interfaces/window_tree.mojom.h"
@@ -26,34 +23,23 @@
 
 namespace {
 
-void BindMusConnectionOnMainThread(
-    uint32_t routing_id,
-    ui::mojom::WindowTreeClientRequest request) {
-  RenderWidgetMusConnection* connection =
-      RenderWidgetMusConnection::GetOrCreate(routing_id);
-  connection->Bind(std::move(request));
-}
-
 // This object's lifetime is managed by MojoShellConnection because it's a
 // registered with it.
 class RenderWidgetWindowTreeClientFactoryImpl
-    : public ConnectionFilter,
+    : public shell::Service,
       public shell::InterfaceFactory<
           mojom::RenderWidgetWindowTreeClientFactory>,
       public mojom::RenderWidgetWindowTreeClientFactory {
  public:
   RenderWidgetWindowTreeClientFactoryImpl() {
     DCHECK(MojoShellConnection::GetForProcess());
-
-    main_thread_task_runner_ = base::ThreadTaskRunnerHandle::Get();
   }
 
   ~RenderWidgetWindowTreeClientFactoryImpl() override {}
 
  private:
-  // ConnectionFilter implementation:
-  bool OnConnect(shell::Connection* connection,
-                 shell::Connector* connector) override {
+  // shell::Service implementation:
+  bool OnConnect(shell::Connection* connection) override {
     connection->AddInterface<mojom::RenderWidgetWindowTreeClientFactory>(this);
     return true;
   }
@@ -68,13 +54,12 @@
   // mojom::RenderWidgetWindowTreeClientFactory implementation.
   void CreateWindowTreeClientForRenderWidget(
       uint32_t routing_id,
-      ui::mojom::WindowTreeClientRequest request) override {
-    main_thread_task_runner_->PostTask(
-        FROM_HERE, base::Bind(&BindMusConnectionOnMainThread, routing_id,
-                              base::Passed(&request)));
+      mojo::InterfaceRequest<ui::mojom::WindowTreeClient> request) override {
+    RenderWidgetMusConnection* connection =
+        RenderWidgetMusConnection::GetOrCreate(routing_id);
+    connection->Bind(std::move(request));
   }
 
-  scoped_refptr<base::SequencedTaskRunner> main_thread_task_runner_;
   mojo::BindingSet<mojom::RenderWidgetWindowTreeClientFactory> bindings_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetWindowTreeClientFactoryImpl);
@@ -82,10 +67,9 @@
 
 }  // namespace
 
-void CreateRenderWidgetWindowTreeClientFactory(
-    MojoShellConnection* connection) {
-  connection->AddConnectionFilter(
-      base::MakeUnique<RenderWidgetWindowTreeClientFactoryImpl>());
+void CreateRenderWidgetWindowTreeClientFactory() {
+  MojoShellConnection::GetForProcess()->MergeService(
+      base::WrapUnique(new RenderWidgetWindowTreeClientFactoryImpl));
 }
 
 }  // namespace content