[DevTools] Move DevToolsWindow testing code to a separate class.

chrome/test/base/ui_test_utils.h

Index: chrome/test/base/ui_test_utils.h
diff --git a/chrome/test/base/ui_test_utils.h b/chrome/test/base/ui_test_utils.h
index 7c15ce8bce597720801de2062b7e349c0db9f85a..9e690d1534ad604a9efc066ee396884e928eba93 100644
--- a/chrome/test/base/ui_test_utils.h
+++ b/chrome/test/base/ui_test_utils.h
@@ -28,7 +28,6 @@
 
 class AppModalDialog;
 class Browser;
-class DevToolsWindow;
 class LocationBar;
 class Profile;
 class SkBitmap;
@@ -111,9 +110,6 @@ void NavigateToURLBlockUntilNavigationsComplete(Browser* browser,
                                                 const GURL& url,
                                                 int number_of_navigations);
 
-// Blocks until DevTools window is loaded.
-void WaitUntilDevToolsWindowLoaded(DevToolsWindow* window);
-
 // Generate the file path for testing a particular test.
 // The file for the tests is all located in
 // test_root_directory/dir/<file>