Create only one ContextFactory in content unit tests

content/public/test/test_renderer_host.cc

Index: content/public/test/test_renderer_host.cc
diff --git a/content/public/test/test_renderer_host.cc b/content/public/test/test_renderer_host.cc
index 35d4ca6e77d892f42b351e309739d0520510e535..e9e41ab06921b2fd39dc8a11e7be8b63eff51e6d 100644
--- a/content/public/test/test_renderer_host.cc
+++ b/content/public/test/test_renderer_host.cc
@@ -8,6 +8,7 @@
 
 #include "base/run_loop.h"
 #include "build/build_config.h"
+#include "content/browser/compositor/test/no_transport_image_transport_factory.h"
 #include "content/browser/frame_host/navigation_entry_impl.h"
 #include "content/browser/renderer_host/render_view_host_factory.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
@@ -190,11 +191,13 @@ void RenderViewHostTestHarness::SetUp() {
 #if defined(OS_WIN)
   ole_initializer_.reset(new ui::ScopedOleInitializer());
 #endif
+#if !defined(OS_ANDROID)
+  ImageTransportFactory::InitializeForUnitTests(
+      base::WrapUnique(new NoTransportImageTransportFactory));
+#endif
 #if defined(USE_AURA)
-  // The ContextFactory must exist before any Compositors are created.
-  bool enable_pixel_output = false;
   ui::ContextFactory* context_factory =
-      ui::InitializeContextFactoryForTests(enable_pixel_output);
+      ImageTransportFactory::GetInstance()->GetContextFactory();
 
   aura_test_helper_.reset(
       new aura::test::AuraTestHelper(base::MessageLoopForUI::current()));
@@ -242,6 +245,12 @@ void RenderViewHostTestHarness::TearDown() {
                             FROM_HERE,
                             browser_context_.release());
   thread_bundle_.reset();
+
+#if !defined(OS_ANDROID)
+    // RenderWidgetHostView holds on to a reference to SurfaceManager, so it
+    // must be shut down before the ImageTransportFactory.
+    ImageTransportFactory::Terminate();
+#endif
 }
 
 BrowserContext* RenderViewHostTestHarness::CreateBrowserContext() {