Support notifications

[fhd]

Background

#1107 will add support for notifications to libadblockplus.

What to change

Use the new API to show notifications. We have a range of options for how this can look in IE, something similar to how it looks in Firefox would probably be best.

Note for testers

In addition to the notification functionality please pay attention to the uninstalling (it also happens during the update procedure) of ABP for IE. The change in this issue can affect the termination of the engine (background ABP process, AdblockPlusEngine.exe).

To test the notification functionality one can use Fiddler and modify OnBeforeResponse handler by adding

if (oSession.uriContains("notification.json")) {
  var respBody = '{"notifications": [{"id": "myId", "title": "Update Adblock Plus", "message": "A new version of Adblock Plus is ready to be installed. Do you want to <a>install it now</a>?", "links": ["http://adblockplus.org"]}],"version": "201502031430" }';
   oSession.utilSetResponseBody(respBody);
 }

Take into account that the first download notification request is executed in about one minute if there is nothing about notifications in prefs.json.

While testing the notification please pay attention that

• there is no any prompting dialog to launch AdblockPlusEngine.exe (Now it always runs at Meidum IL, one can ensure about that using some advanced task manager like ProcessExplorer from Windows Sysinternals)
• the link in the notification is opened on mouse-click
• the notification window is correctly displayed on different DPI settings
• it works on the whole range of platforms Windows[XP-10] x IE[8-11].

[oleksandr]

Notification requests are now made by ABP for IE since #1557 is fixed now. We now need to implement some UI to display notifications to the user.

[sergz]

Remove #1107 because it's already not blocking and having it opened one cannot close this issue.