Disable AppList sync by default on non Chrome OS

ui/app_list/app_list_switches.cc

Index: ui/app_list/app_list_switches.cc
diff --git a/ui/app_list/app_list_switches.cc b/ui/app_list/app_list_switches.cc
index c1e05026b1f152e69fcea4f547bec8359b0e8287..31842f2563ba4d6eda73de4754602f7edbdaf9dd 100644
--- a/ui/app_list/app_list_switches.cc
+++ b/ui/app_list/app_list_switches.cc
@@ -9,8 +9,8 @@
 namespace app_list {
 namespace switches {
 
-// If set, folder will be disabled in app list UI.
-const char kDisableFolderUI[] = "disable-app-list-folder-ui";
+// Disables syncing of the app list independent of extensions.
+const char kDisableSyncAppList[] = "disable-sync-app-list";
 
 // If set, the voice search is disabled in app list UI.
 const char kDisableVoiceSearch[] = "disable-app-list-voice-search";
@@ -29,13 +29,24 @@ const char kEnableExperimentalAppListPosition[] =
 // when the hotword is recognized.
 const char kEnableHotwordAlwaysOn[] = "enable-app-list-hotword-always-on";
 
-// Folder UI is enabled by default.
-bool IsFolderUIEnabled() {
-#if !defined(OS_MACOSX)
-  return !CommandLine::ForCurrentProcess()->HasSwitch(kDisableFolderUI);
+// Enables syncing of the app list independent of extensions.
+const char kEnableSyncAppList[] = "enable-sync-app-list";
+
+bool IsAppListSyncEnabled() {
+#if defined(OS_CHROMEOS)
+  return !CommandLine::ForCurrentProcess()->HasSwitch(kDisableSyncAppList);
 #else
-  return false;
+  return CommandLine::ForCurrentProcess()->HasSwitch(kEnableSyncAppList);
+#endif
+}
+
+bool IsFolderUIEnabled() {
+#if defined(OS_MACOSX)
+  return false;  // Folder UI not implemented for OSX
 #endif
+  // Folder UI is available only when AppList sync is enabled, and should
+  // not be disabled separately.
+  return IsAppListSyncEnabled();
 }
 
 bool IsVoiceSearchEnabled() {