Bug 1061446 - [Dolphin][v1.4]Drag and drop an icon to a new page,the phone will always go to the new page automatically

The purpose of setDisabledCheckingLimits is to disable checkLimits when homescreen is making transition between pages. This can be traced long back to the 1st commit of the homescreen app in the commit df5f425, at line 591 and line 616 in apps/homescreentef/js/grid.js.

However, setDisabledCheckingLimits (at line 149) is invoked without page transition when the icon is placed at the right screen limit, which is unnecessary and causes the loop. What we need is to move the setDisabledCheckingLimits call to the 'if (pageHelper.getNext())' block.
Bug 1034279 - USSD messages not displayed if user leaves Dialer while sending r=etienne

I took the opportunity to re-enable a unit test

(cherry picked from commit 46bad9d7f31cbc79a4551b011529156ba8f1f8c7)

Conflicts:
	apps/communications/dialer/test/unit/mmi_ui_test.js

Signed-off-by: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Merge pull request #23839 from begeeben/1061446_drag_and_drop

Bug 1061446 - [Dolphin][v1.4]Drag and drop an icon to a new page,the phone will always go to the new page automatically, r=:crdlc