fxLayoutGap not working with fxLayout fxFlexOrder

[parindholakia]

Bug:

fxLayoutGap does not work when fxFlexOrder is given with responsive breakpoints.Initially it is rendered properly. But when the screen is resized,fxLayoutGap does not work.

What is the expected behavior?

fxLayoutGap should work when screen is resized.

What are the steps to reproduce?

stackblitz

1. Initial Page rendered.

2. After page resize
   

3. normal mode after resizing.

[CaerusKaru]

Related to #606, I have some fixes in mind that we'll try to get in by beta.16

[m-henderson]

@CaerusKaru do you need help with this issue? if so, could you give me a starting point?

[CaerusKaru]

@m-henderson If you want to pitch in, that'd be great! The starting point most likely involves adding a MutationObserver in the LayoutGapDirective that watches all immediate children for changes, particularly relating to ordering (essentially re-running the initialization logic).