services/ui: Allow injecting the IO thread task runner for gpu channel.

chrome/browser/ui/views/chrome_browser_main_extra_parts_views.cc

Index: chrome/browser/ui/views/chrome_browser_main_extra_parts_views.cc
diff --git a/chrome/browser/ui/views/chrome_browser_main_extra_parts_views.cc b/chrome/browser/ui/views/chrome_browser_main_extra_parts_views.cc
index d897d5de24938f6b1903be7bd892aa4743ad336c..51f88793994053b99ebdb6cc9355630c5a853217 100644
--- a/chrome/browser/ui/views/chrome_browser_main_extra_parts_views.cc
+++ b/chrome/browser/ui/views/chrome_browser_main_extra_parts_views.cc
@@ -10,9 +10,11 @@
 
 #if defined(USE_AURA)
 #include "base/run_loop.h"
+#include "content/public/browser/browser_thread.h"
 #include "content/public/common/mojo_shell_connection.h"
 #include "services/shell/public/cpp/connector.h"
 #include "services/shell/runner/common/client_util.h"
+#include "services/ui/public/cpp/gpu_service.h"
 #include "services/ui/public/cpp/input_devices/input_device_client.h"
 #include "services/ui/public/interfaces/input_devices/input_device_server.mojom.h"
 #include "ui/display/screen.h"
@@ -65,6 +67,9 @@ void ChromeBrowserMainExtraPartsViews::MojoShellConnectionStarted(
 
     window_manager_connection_ = views::WindowManagerConnection::Create(
         connection->GetConnector(), connection->GetIdentity());
+    window_manager_connection_->gpu_service()->SetIOThreadTaskRunner(
+        content::BrowserThread::GetTaskRunnerForThread(
+            content::BrowserThread::IO));
   }
 #endif  // defined(USE_AURA)
 }