Test tidying: use "escape" and "backspace" with eventSender.keyDown()

LayoutTests/editing/selection/context-menu-text-selection.html

Index: LayoutTests/editing/selection/context-menu-text-selection.html
diff --git a/LayoutTests/editing/selection/context-menu-text-selection.html b/LayoutTests/editing/selection/context-menu-text-selection.html
index b25dea8d12c9cf55bc89120524cfbe643d984984..86f4a899713ef6df405e3d567a899def4f3e687b 100644
--- a/LayoutTests/editing/selection/context-menu-text-selection.html
+++ b/LayoutTests/editing/selection/context-menu-text-selection.html
@@ -22,7 +22,7 @@ function test(platform, selectionExpected, result)
     eventSender.mouseMoveTo(x, y);
     eventSender.contextClick();
     // esc key to kill the context menu
-    eventSender.keyDown(String.fromCharCode(0x001B), null);
+    eventSender.keyDown("escape", null);
 
     var resultElement = document.getElementById(result);
     var selectionType = window.getSelection().type;