Horizon 'launch as instance' from a specific volume does not set the volume as default source

[Yang Liu]

Brief Description
-----------------
Select 'Launch as Instance' action from a specific volume, often times the boot source will not automatically point the current volume.

Work around is to select the current volume as boot source manually.

Severity
--------
Minor

Steps to Reproduce
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1. Create a bootable volume and wait till it is available
2. In horizon, switch to a tenant prioject > Volumes > Volumes > select an existing volume > from Actions, select Launch as Instance > navigate to Source
3. change boot source type > abort it without creating an instance
4. Repeat step 2

Expected Behavior
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4. Current volume is automated populated as boot source. i.e., 'Select Boot Source' is set to 'Volume', and current volume is listed in 'Allocated' sources

Actual Behavior
----------------
4. The 'Allocated' field is empty, and 'Select Boot Source' can be Image or Volume
(step 3 is not always needed to reproduce the issue, it seems to happen intermittently on any volume, however, with step3, it almost always reproducible)

Reproducibility
---------------
Intermittent

System Configuration
--------------------
Any

Branch/Pull Time/Commit
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stx.18.10 as of 2018-10-23_01-52-00

Timestamp/Logs
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I didn't find anything valuable in /var/log/horizon.log. And it is easy to reproduce.

[Ghada Khalil (gkhalil)]

Minor gui issue; low priority / does not gate any release

[Ramaswamy Subramanian (rsubrama)]

No progress on this bug for more than 2 years. Candidate for closure.

If there is no update, this issue is targeted to be closed as 'Won't Fix' by March 8th.

[Ramaswamy Subramanian (rsubrama)]

Changing the status to 'Won't Fix' as there is no activity.