Update SplitString calls to new form

ash/test/display_manager_test_api.cc

Index: ash/test/display_manager_test_api.cc
diff --git a/ash/test/display_manager_test_api.cc b/ash/test/display_manager_test_api.cc
index 77d88ec007e7139c0eb7ced216b99989d18793ca..9bad8917888e9360a067611362e96abc14066adf 100644
--- a/ash/test/display_manager_test_api.cc
+++ b/ash/test/display_manager_test_api.cc
@@ -34,8 +34,8 @@ std::vector<DisplayInfo> CreateDisplayInfoListFromString(
     const std::string specs,
     DisplayManager* display_manager) {
   std::vector<DisplayInfo> display_info_list;
-  std::vector<std::string> parts;
-  base::SplitString(specs, ',', &parts);
+  std::vector<std::string> parts = base::SplitString(
+      specs, ",", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
   size_t index = 0;
 
   DisplayManager::DisplayList list =