[Extensions] Simplify Extension Keybinding API Tests

chrome/test/data/extensions/api_test/keybinding/basics/manifest.json

 {
-  "name": "A browser action with no icon that makes the page red",
+  "name": "A browser action with no icon that sends a test message",
   "version": "1.0",
   "manifest_version": 2,
   "background": {
     "scripts": ["background.js"]
   },
   "permissions": ["activeTab"],
   "browser_action": {
-    "default_title": "Make this page red",
+    "default_title": "Send message",
     "default_icon": "icon.png"
   },
   "commands": {
     "toggle-feature": {
       "suggested_key": {
         "windows": "Ctrl+Shift+Y",
         "mac": "MacCtrl+Shift+Y",
         "linux": "Ctrl+Shift+Y",
         "chromeos": "Ctrl+Shift+Y",
         "default": "Ctrl+Shift+Y"
       },
       "description": "Toggle feature foo"
     },
     "_execute_browser_action": {
       "suggested_key": {
         "mac": "MacCtrl+Shift+F",
         "default": "Ctrl+Shift+F"
       }
     }
   }
 }