Summary: This diff cleans up the parent / owner references for children of ReactShadowNode / YogaNode during cloning. The reason of this behavior is to avoid retaining every generation of trees during cloning. This fixes a memory leak detected when running the ProgressBarExample.android.js in catalyst app
Reviewed By: fkgozali
Differential Revision: D8019894
fbshipit-source-id: b0d38f0c836ffec534f64fa1adbd7511ecf3473d