Respect --profile-directory flag when used with --show-app-list flag.

This CL allows specification of the profile to show the app list for when
launching the app list via the command line.

Currently --show-app-list always uses the last used app list profile, but we
want to allow testers to more easily load the app list for a particular
profile.

On Windows, this can be used for making shorcuts to a particular profile's
app list but this will always bind to the main shortcut due to the app id.

BUG=400874

Review URL: https://codereview.chromium.org/500333002

Cr-Commit-Position: refs/heads/master@{#292291}

chrome/browser/ui/startup/startup_browser_creator.cc

@@ -728,6 +728,11 @@ bool HasPendingUncleanExit(Profile* profile) {
 
 base::FilePath GetStartupProfilePath(const base::FilePath& user_data_dir,
                                      const CommandLine& command_line) {
+  if (command_line.HasSwitch(switches::kProfileDirectory)) {
+    return user_data_dir.Append(
+        command_line.GetSwitchValuePath(switches::kProfileDirectory));
+  }
+
   // If we are showing the app list then chrome isn't shown so load the app
   // list's profile rather than chrome's.
   if (command_line.HasSwitch(switches::kShowAppList)) {
@@ -735,11 +740,6 @@ base::FilePath GetStartupProfilePath(const base::FilePath& user_data_dir,
         GetProfilePath(user_data_dir);
   }
 
-  if (command_line.HasSwitch(switches::kProfileDirectory)) {
-    return user_data_dir.Append(
-        command_line.GetSwitchValuePath(switches::kProfileDirectory));
-  }
-
   return g_browser_process->profile_manager()->GetLastUsedProfileDir(
       user_data_dir);
 }