Remove calls to deprecated MessageLoop methods on Windows and Linux.

ui/app_list/views/apps_grid_view_unittest.cc

Index: ui/app_list/views/apps_grid_view_unittest.cc
diff --git a/ui/app_list/views/apps_grid_view_unittest.cc b/ui/app_list/views/apps_grid_view_unittest.cc
index e0b730cd2bbfd484e9ec34b87dc6f197b06cdb4d..e6eadf3e6e42c9a77e949b3b7055a26626571654 100644
--- a/ui/app_list/views/apps_grid_view_unittest.cc
+++ b/ui/app_list/views/apps_grid_view_unittest.cc
@@ -13,6 +13,7 @@
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/message_loop/message_loop.h"
+#include "base/run_loop.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "build/build_config.h"
@@ -53,7 +54,7 @@ class PageFlipWaiter : public PaginationModelObserver {
     DCHECK(!wait_);
     wait_ = true;
 
-    ui_loop_->Run();
+    base::RunLoop().Run();
     wait_ = false;
   }