ui: No more TestCompositor. Use NullDraw contexts in unit tests.

ui/aura/test/aura_test_helper.cc

Index: ui/aura/test/aura_test_helper.cc
diff --git a/ui/aura/test/aura_test_helper.cc b/ui/aura/test/aura_test_helper.cc
index a101eda42fabe530a803efc6387dd25586fb63d9..7c03a051cab45abd6133d0b12a689a83f67b7d94 100644
--- a/ui/aura/test/aura_test_helper.cc
+++ b/ui/aura/test/aura_test_helper.cc
@@ -22,7 +22,6 @@
 #include "ui/compositor/compositor.h"
 #include "ui/compositor/layer_animator.h"
 #include "ui/compositor/scoped_animation_duration_scale_mode.h"
-#include "ui/compositor/test/context_factories_for_test.h"
 #include "ui/gfx/screen.h"
 
 #if defined(USE_X11)
@@ -54,12 +53,9 @@ AuraTestHelper::~AuraTestHelper() {
       << "AuraTestHelper::TearDown() never called.";
 }
 
-void AuraTestHelper::SetUp(bool allow_test_contexts) {
+void AuraTestHelper::SetUp() {
   setup_called_ = true;
 
-  // The ContextFactory must exist before any Compositors are created.
-  ui::InitializeContextFactoryForTests(allow_test_contexts);
-
   Env::CreateInstance();
   // Unit tests generally don't want to query the system, rather use the state
   // from RootWindow.
@@ -108,8 +104,6 @@ void AuraTestHelper::TearDown() {
   ui::ShutdownInputMethodForTesting();
 
   Env::DeleteInstance();
-
-  ui::TerminateContextFactoryForTests();
 }
 
 void AuraTestHelper::RunAllPendingInMessageLoop() {