Avoid loading the last used browser profile in app_controller_mac when it's not needed.

apps/app_shim/chrome_main_app_mode_mac.mm

Index: apps/app_shim/chrome_main_app_mode_mac.mm
diff --git a/apps/app_shim/chrome_main_app_mode_mac.mm b/apps/app_shim/chrome_main_app_mode_mac.mm
index 2c13ba23c29ec3de0afd7e68c465542fb17e6ced..c1271c1999417a99e9599a16b118fdc6351ce9a6 100644
--- a/apps/app_shim/chrome_main_app_mode_mac.mm
+++ b/apps/app_shim/chrome_main_app_mode_mac.mm
@@ -605,8 +605,14 @@ int ChromeAppModeStart(const app_mode::ChromeAppModeInfo* info) {
     ProcessSerialNumber psn;
     CommandLine command_line(CommandLine::NO_PROGRAM);
     command_line.AppendSwitch(switches::kSilentLaunch);
-    command_line.AppendSwitchPath(switches::kProfileDirectory,
-                                  info->profile_dir);
+
+    if (info->app_mode_id == app_mode::kAppListModeId) {
+      command_line.AppendSwitch(switches::kShowAppList);

[Nico, 2014/01/14 02:06:34]

I didn't get why this is needed.

[tapted, 2014/01/14 04:02:28]

Added a comment. This is the "Chrome not running" branch: passing
--show-app-list allows browser startup codepaths to load the best profile.
Otherwise, it's not known until the UI runloop has spun up, and the shim has
connected to the IPC domain socket.

+    } else {
+      command_line.AppendSwitchPath(switches::kProfileDirectory,
+                                    info->profile_dir);
+    }
+
     bool success =
         base::mac::OpenApplicationWithPath(base::mac::OuterBundlePath(),
                                            command_line,