Never launch a new window when --no-startup-window is specified.

chrome/browser/ui/startup/startup_browser_creator.cc

Index: chrome/browser/ui/startup/startup_browser_creator.cc
diff --git a/chrome/browser/ui/startup/startup_browser_creator.cc b/chrome/browser/ui/startup/startup_browser_creator.cc
index 238fdb5ac570c5beaf5388ee7fc075978126bbd6..50e42fa6d6e0f832637dbe58b3f6a5664ebf3881 100644
--- a/chrome/browser/ui/startup/startup_browser_creator.cc
+++ b/chrome/browser/ui/startup/startup_browser_creator.cc
@@ -600,6 +600,11 @@ bool StartupBrowserCreator::ProcessCmdLineImpl(
     silent_launch = true;
   }
 
+  // If --no-startup-window is specified and Chrome is already running then do
+  // not open a new window.
+  if (!process_startup && command_line.HasSwitch(switches::kNoStartupWindow))
+    silent_launch = true;
+
   // If we don't want to launch a new browser window or tab we are done here.
   if (silent_launch)
     return true;