Pressing Tab focus on the last property's value when focusing on the 'Update' in 'Edit Entity' dialog

[v-xuanzh]

Storage Explorer Version: 1.3.0
Platform/OS Version: Windows 10/MacOS High Sierra/ Linux Ubuntu 16.04
Architecture: ia32/x64
Build Number: 20180706.1
Commit: 99a0e75f
Regression From: Previous release 1.2.0(20180604.2)

Steps to Reproduce:

1. Go to subscription -> Storage Accounts.
2. Create a new table -> Add an entity with only Partition Key and Row Key -> Click 'Edit' button on the toolbar.
3. Focus on 'Update' using Tab -> Press Tab again.
4. Check the next focus.

Expected Experience:

The first property name is focused.

Actual Experience:

The last property's value is focused.

[craxal]

Looks like this is just a symptom of the "extra tab in dialogs" bug we keep running into (see #162). What's happening here is the window (not the text input) has focus. If you closely, the border is not focused. For some reason, the text of the last text input that had focus is getting highlighted when the window gets focus.