Merge pull request #8756 from mozsquib/email-activesync-item-estimate

Bug 853602 - [email/activesync] GetItemEstimate fails for older versions of Exchange(cherry picked from commit 29007ac85a48188e4dc2438628dee7bfb8e38cbd)
Bug 849988 - Implement support for a removable property for preinstalled apps to define if the app can be uninstalled or not r=ferjm
(cherry picked from commit 99267614620b8c09a82711d4ded14a87211d263b)
Merge pull request #8383 from JonHylands/jhylands-826249-master

826249 - Increase gallery exposure control responsiveness r=djf(cherry picked from commit a28105c34ae2b5f879e76894b8d69f5c2d1f78be)