Summary:
In YogaKit, nodes are not dirtied when `sizeThatFits` of leaf nodes change. This makes it difficult to reuse views like `UILabel` when their content (text) changes. I wrote a failing test to prove it and wrote a fix by caching the latest value of `sizeThatFits` in `YGNodeBridge` and checking for changes in `YGAttachNodesFromViewHierachy` (renamed to `YGUpdateNodesFromViewHierachy` to make it clear it's not simply reattaching nodes anymore). When a new size is detected, I call `YGNodeMarkDirty` on the leaf node.
**Unfortunately**, this makes another test fail for no logical reason (`testThatViewNotIncludedInFirstLayoutPassAreIncludedInSecond`). Either there's something I don't understand or I've un-advertedly unearthed a bug in the C implementation, but in what case would setting a node dirty make the layout return a different size?
Closes https://github.com/facebook/yoga/pull/308
Reviewed By: emilsjolander
Differential Revision: D4378826
Pulled By: dshahidehpour
fbshipit-source-id: cd0640bc863debb9e434370739416e3e33e57a08
29c44e281c