Rename ShellBaseTestCase as WebShellTestCase.

ios/web/shell/test/context_menu_egtest.mm

Index: ios/web/shell/test/context_menu_egtest.mm
diff --git a/ios/web/shell/test/context_menu_egtest.mm b/ios/web/shell/test/context_menu_egtest.mm
index 46f665ee9a630e1202c03450af4303d0ec3cd081..a99f1956a2cc0e40c1a00ab912559daeea246149 100644
--- a/ios/web/shell/test/context_menu_egtest.mm
+++ b/ios/web/shell/test/context_menu_egtest.mm
@@ -16,10 +16,10 @@
 #import "ios/web/public/test/web_view_interaction_test_util.h"
 #import "ios/web/shell/test/app/web_shell_test_util.h"
 #include "ios/web/shell/test/app/web_view_interaction_test_util.h"
-#import "ios/web/shell/test/earl_grey/shell_base_test_case.h"
 #import "ios/web/shell/test/earl_grey/shell_actions.h"
 #import "ios/web/shell/test/earl_grey/shell_earl_grey.h"
 #import "ios/web/shell/test/earl_grey/shell_matchers.h"
+#import "ios/web/shell/test/earl_grey/web_shell_test_case.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
@@ -30,7 +30,7 @@ using testing::ElementToDismissContextMenu;
 using web::WebViewContainingText;
 
 // Context menu test cases for the web shell.
-@interface ContextMenuTestCase : ShellBaseTestCase
+@interface ContextMenuTestCase : WebShellTestCase
 @end
 
 @implementation ContextMenuTestCase