fix strange space at the top when FlexWrap (#522)

[sheckspir]

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[sheckspir]

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[thagikura]

I think this is not a correct way to fix the issue.

Actually some of the tests in FlexboxLayoutMangerTests are failing after patching this PR.

Couldn't look into the issue carefully, but I guess what needs to be cared is not whether the main axis direction is horizontal, but whether the flex wrap is nowrap.

[thagikura]

Thanks for the PR!

But looks like existing tests are failing, also is it possible to add a test to FlexboxLayoutManager to verify the fix?

[sheckspir]

@thagikura Yes, you was right. It was a bad way to resolve it. I looked on it some more, and I saw, that you change OrientationHelper for a situation, when flexWrap != NOWRAP. It makes sense. Because scrolling, in this case, goes otherways
But we have a small problem. FlexboxLayoutManager calculate offset position from leftPadding, but should use topPadding (or bottomPadding for reverse)
So I used SubOrientationHelper as you did in method assignFromView(View anchor)

[thagikura]

Sorry for the delayed replay..

Thanks for the new commit! Yup, the fix looks like what I intended. But noticed that FlexboxLayoutManager.testDrawDirtyFlexLine_multi_viewTypes_direction_row fails consistently.

Haven't spotted what causes the failure, but is it possible to check on your end, too?