Remove entity length condition

Rendering performance stalls before this limit anyway.
Revert "Add URL flag for translate3d"

This reverts commit 228dfbe9934ffe79e1f72812a026075e1205d5de.
Simplify
Move flush to context
Graph#rebase must invalidate transients
Comment why _childNodes needn't be updated
Revert "Cache centroid"

Causes misplaced labels, suspect due to rounding artifacts.

This reverts commit 5344bdea26d83ba26a095fe43c50352a4d941917.