trunk: Screen Resolution showing as unknown for IE visitors in Piwik 1.7.2 RC8 #3141

Since switching from version 1.7.1 to 1.7.2_RC8 I've noticed a lot of the screen resolutions show as unknown whereas before I did not have this problem.

unknown     487
1366x768    72
1680x1050   41
320x480     50
1280x800    48

They all seem to be IE based browsers with few exceptions, attaching section of piwik_log_visit table as CSV for more details

A byproduct of this problem is that all unknown screen resolutions are being classified as Mobile Screen types, resulting in a majority of the screen types being mobile when they should be in a minority:

Mobile  540
Wide    273
Normal  90
Dual    1

Attachment: Section of log_visit database as CSV
piwik_log_visit_unknown.csv

Problem is in piwik.js

This is since detectBrowserFeatures() sets res and due to the new regex check that doesnt call the function if it detects "MSIE" in useragent (Row 1977 in https://github.com/piwik/piwik/blob/master/js/piwik.js).

I don't know how to compress .js like it's done here so could use some help.

Haven't found where unknown screen resolution defaults to mobile yet.

I don't know the routines for suggesting changes here so if anyone wants to grab this and improve/move forward I would be thankful.

Suggested changes for piwik/plugins/UserSettings/functions.php
http://pastebin.com/YG6Btb3Y

Suggested changes for piwik/piwik.js
http://pastebin.com/uGFPXryM
Should be looked over for optimization

Nice catch!

(In [6256]) refs #3141

This was a regression from #2962.