Don't focus a profile by default in the User Manager

When switching users, we used to focus the profile that initiated the
action. This causes weird skip-a-roos if you try to tab to a different
pod before the forced focus completes, so don't focus any pods by default.

BUG=410718
TEST=Start Chrome with --enable-new-menu. Click on "Switch Person". The
User Manager should come up, no pods should be focused, and if you try
to left arrow or right arrow really fast, the pods shouldn't jump focus.

Review URL: https://codereview.chromium.org/546953002

Cr-Commit-Position: refs/heads/master@{#293767}

chrome/browser/ui/cocoa/profiles/profile_chooser_controller.mm

@@ -895,7 +895,7 @@ class ActiveProfileObserverBridge : public AvatarMenuObserver,
 }
 
 - (IBAction)showUserManager:(id)sender {
-  chrome::ShowUserManager(browser_->profile()->GetPath());
+  chrome::ShowUserManager(base::FilePath());
   [self postActionPerformed:
       ProfileMetrics::PROFILE_DESKTOP_MENU_OPEN_USER_MANAGER];
 }

chrome/browser/ui/views/profiles/profile_chooser_view.cc

@@ -710,7 +710,7 @@ void ProfileChooserView::ButtonPressed(views::Button* sender,
     if (browser_->profile()->IsGuestSession())
       profiles::CloseGuestProfileWindows();
     else
-      chrome::ShowUserManager(browser_->profile()->GetPath());
+      chrome::ShowUserManager(base::FilePath());
     PostActionPerformed(ProfileMetrics::PROFILE_DESKTOP_MENU_OPEN_USER_MANAGER);
   } else if (sender == go_incognito_button_) {
     DCHECK(ShouldShowGoIncognito());
@@ -758,7 +758,7 @@ void ProfileChooserView::ButtonPressed(views::Button* sender,
   } else if (sender == add_person_button_) {
     ProfileMetrics::LogProfileNewAvatarMenuNotYou(
         ProfileMetrics::PROFILE_AVATAR_MENU_NOT_YOU_ADD_PERSON);
-    chrome::ShowUserManager(browser_->profile()->GetPath());
+    chrome::ShowUserManager(base::FilePath());
   } else if (sender == disconnect_button_) {
     ProfileMetrics::LogProfileNewAvatarMenuNotYou(
         ProfileMetrics::PROFILE_AVATAR_MENU_NOT_YOU_DISCONNECT);