Group commandline settings in UI test and in process browser test.

chrome/test/in_process_browser_test.h

Index: chrome/test/in_process_browser_test.h
===================================================================
--- chrome/test/in_process_browser_test.h	(revision 65553)
+++ chrome/test/in_process_browser_test.h	(working copy)
@@ -149,6 +149,9 @@
   // Quits all open browsers and waits until there are no more browsers.
   void QuitBrowsers();
 
+  // Config commandlines that are common to InProcessBrowserTests.
+  void PrepareCommonInProcessBrowserTestCommandLine(CommandLine* arguments);
+
   // Browser created from CreateBrowser.
   Browser* browser_;