Center and change the aspect ratio for the experimental app list. [Win]

ui/app_list/app_list_constants.cc

Index: ui/app_list/app_list_constants.cc
diff --git a/ui/app_list/app_list_constants.cc b/ui/app_list/app_list_constants.cc
index 43f140d9dd07539a8e6a3bc25a566dd852badb65..c34004a0f10a62601eec853cf30b1c07753d9537 100644
--- a/ui/app_list/app_list_constants.cc
+++ b/ui/app_list/app_list_constants.cc
@@ -58,6 +58,10 @@ const int kPreferredCols = 4;
 const int kPreferredRows = 4;
 const int kPreferredIconDimension = 48;
 
+// Preferred number of columns and rows in the experimental app list apps grid.
+const int kExperimentalPreferredCols = 6;
+const int kExperimentalPreferredRows = 3;
+
 // Number of the top items in a folder, which are shown inside the folder icon
 // and animated when opening and closing a folder.
 const size_t kNumFolderTopItems = 4;