Disable fork button for view_only user

[tonyjiangh]

Fix #2459

Disabled view

With cursor disabled as well

Before/After

Permission	Before (Show Data Only)	After (Show Data Only)	Before(Edit Source)	After(Edit Source)
Creator/Admin	Active	Disabled	Active	Active
Full Access	Active	Disabled	Active	Active
View Only	Active(returns 403 response)	Disabled	Active(returns 403 response)	Disabled

Tested over Firefox 59.0.2

[kravets-levko]

@tonyjiangh I think, this is a better place for this CSS. @kocsmy - WDYT?

[kravets-levko]

In addition - there is a variable for disabled dropdown items

[kocsmy]

Yes, we have a disabled class for li already. We'll need to adjust the color a bit more gray to indicate it's disabled.

[arikfr]

Thanks! Why disable it (for creator/admin) in data only mode?

[kravets-levko]

@arikfr As I see, @tonyjiangh didn't implement any new logic - he uses the same condition (query.id === undefined || !canForkQuery()), so Fork item will not be disabled in data only mode (as it works now). It's just a UI improvement - add style to indicate that item is disabled.

[tonyjiangh]

@kravets-levko
Thanks for the review. I'll try to fix the position for css.

@arikfr @kravets-levko
No, I didn't implement any new logic. But fork in data only mode will be disabled with the current version of this fix.
Here's why:
We're using client/app/pages/queries/view.js for data only view,
and client/app/pages/queries/source-view.js for query source view.
Currently $scope.canForkQuery() is only implemented for the later.

It thought this was intentional. But based on the conversation above, I guess it's not. I'll fix that too.

[tonyjiangh]

Before/After

Permission	Before (Show Data Only)	After (Show Data Only)	Before(Edit Source)	After(Edit Source)
Creator/Admin	Active	Active	Active	Active
Full Access	Active	Active	Active	Active
View Only	Active(returns 403 response)	Disabled	Active(returns 403 response)	Disabled

[kravets-levko]

LGTM 👍

[arikfr]

Thanks!