Attempt to fix ash tests on Chrome OS valgrind

ash/test/ash_test_helper.cc

Index: ash/test/ash_test_helper.cc
diff --git a/ash/test/ash_test_helper.cc b/ash/test/ash_test_helper.cc
index 060f8c1bee54bb80d096b65b204b0b9e5c52ca28..d4c912974f71db0a176df14f913f2fe1a0f67b37 100644
--- a/ash/test/ash_test_helper.cc
+++ b/ash/test/ash_test_helper.cc
@@ -28,6 +28,7 @@
 #include "ui/compositor/test/context_factories_for_test.h"
 #include "ui/message_center/message_center.h"
 #include "ui/wm/core/capture_controller.h"
+#include "ui/wm/core/cursor_manager.h"
 
 #if defined(OS_CHROMEOS)
 #include "chromeos/audio/cras_audio_handler.h"
@@ -113,6 +114,10 @@ void AshTestHelper::SetUp(bool start_session) {
   }
   ShellContentState::SetInstance(content_state);
 
+  // Reset the global state for the cursor manager. This includes the
+  // last cursor visibility state, etc.
+  wm::CursorManager::ResetState();
+
   ShellInitParams init_params;
   init_params.delegate = test_shell_delegate_;
   init_params.context_factory = context_factory;