Ensure guest mode browser can activate the correct window.

chrome/browser/app_controller_mac.mm

Index: chrome/browser/app_controller_mac.mm
diff --git a/chrome/browser/app_controller_mac.mm b/chrome/browser/app_controller_mac.mm
index 093610797a5221df83fcbeae9bee1c8465431c5b..b91f755e699e3a39e78af27ca3c2793fc5cfff06 100644
--- a/chrome/browser/app_controller_mac.mm
+++ b/chrome/browser/app_controller_mac.mm
@@ -123,7 +123,8 @@ bool g_is_opening_new_window = false;
 // not possible. If the last active browser is minimized (in particular, if
 // there are only minimized windows), it will unminimize it.
 Browser* ActivateBrowser(Profile* profile) {
-  Browser* browser = chrome::FindLastActiveWithProfile(profile,
+  Browser* browser = chrome::FindLastActiveWithProfile(
+      profile->IsGuestSession() ? profile->GetOffTheRecordProfile() : profile,

[bcwhite, 2014/07/23 14:51:37]

Note that an OTRProfile is not independent but associated with a regular
profile.  You'll want to be sure that (a) FindLastActiveWithProfile() can find
an incognito browser via an OTR profile pointer and that (b) it never returns a
regular browser with the primary profile.

       chrome::HOST_DESKTOP_TYPE_NATIVE);
   if (browser)
     browser->window()->Activate();