Add tests for measure caching
Add tests for measure caching

Summary: Measure caching is a crucial optimization to css-layout which re-uses the output of the measure function if possible. This logic was never covered by tests.

Reviewed By: lucasr

Differential Revision: D3790915

fbshipit-source-id: 7fe6d5ebb1303d3186d24d15e401901bc7c8ecdb

facebook/css-layout,yihuang/css-layout,facebook/css-layout,yihuang/css-layout,rmarinho/yoga,yihuang/css-layout,yihuang/css-layout,rmarinho/yoga,facebook/css-layout,rmarinho/yoga,yihuang/css-layout,facebook/yoga,yihuang/css-layout,yihuang/css-layout,rmarinho/yoga,facebook/yoga,rmarinho/yoga,facebook/yoga,facebook/css-layout,facebook/yoga,facebook/yoga,yihuang/css-layout,facebook/css-layout,yihuang/css-layout,facebook/css-layout,yihuang/css-layout,rmarinho/yoga,rmarinho/yoga,facebook/yoga,facebook/css-layout,facebook/yoga,rmarinho/yoga,rmarinho/yoga,rmarinho/yoga,facebook/yoga,facebook/css-layout,facebook/css-layout,facebook/yoga,facebook/yoga