The Gravity 3 is just a search bar. It has been defined as being a malware and an immediate removal is recommended. Try using Revo Uninstaller. Even if it can't uninstall the application normally, it will force it to uninstall by wiping out all traces of its presence from the system.
After that, try running AdwCleaner to make sure that there are no leftover rogue registry keys or toolbars in your system.
To clear the search results, simply access the Settings of the toolbar then press on Clear data. If you still have the package, remove it and then re-install it, but scan it against an antivirus.
