GN: Get os="chromeos" use_ozone=true to compile

ui/base/BUILD.gn

Index: ui/base/BUILD.gn
diff --git a/ui/base/BUILD.gn b/ui/base/BUILD.gn
index 24830dabdb33105d3424c4b65b4e72ed090088da..dbef91dd79441948d0d38407b87041ba2fba754a 100644
--- a/ui/base/BUILD.gn
+++ b/ui/base/BUILD.gn
@@ -757,16 +757,6 @@ test("ui_unittests") {
       "webui/web_ui_util_unittest.cc",
       "x/selection_requestor_unittest.cc",
     ]
-
-    if (!use_x11) {
-      if (is_chromeos) {
-        # These were already removed in the chromeos case.
-        sources -= [
-          "ime/chromeos/character_composer_unittest.cc",
-          "ime/input_method_chromeos_unittest.cc",
-        ]
-      }
-    }
   }
 
   if (build_ime) {
@@ -782,6 +772,13 @@ test("ui_unittests") {
     if (use_x11) {
       sources += [ "ime/composition_text_util_pango_unittest.cc" ]
     }
+    if (!use_x11 && is_chromeos) {
+      # These were already removed in the non-chromeos case.
+      sources -= [
+        "ime/chromeos/character_composer_unittest.cc",
+        "ime/input_method_chromeos_unittest.cc",
+      ]
+    }
   }
 
   deps = [