Button text does not truncate

Bug report best practices: https://github.com/xamarin/Xamarin.Forms/wiki/Submitting-Issues

Description

Migrating https://bugzilla.xamarin.com/show_bug.cgi?id=59262

Button text does not truncate. If the buttons are in a grid, on Android, it works, on iOS it does not. If the buttons are in a stacklayout, it does not work on both Android and iOS.

Steps to Reproduce

1. Run app Note that on Android, the button text is truncated, and that on iOS it is not.
2. Change MainPage to new stackbutton(); Run App (this uses a stacklayout instead of grid)
3. Note that the button does not truncate on both iOS and Android

Expected Behavior

Button text is truncated

Actual Behavior

Button text is not truncated

Basic Information

• Version with issue: 2.5.0.122203
• Last known good version: N/A
• IDE: VS2017
• Platform Target Frameworks:
  • iOS: yes
  • Android: yes
  • UWP: not tested
• Android Support Library Version: 25
• Nuget Packages: just forms
• Affected Devices: tested on nexus 5x on Android 7, and iphone 5s simulator on iOS 9.3

Screenshots

https://imgur.com/a/NCbN2

Reproduction Link

https://www.dropbox.com/s/d25272c3mzewksf/btnsampletruncate.zip?dl=0