[Fabric] Optimize cloning ShadowTree when animating layout props

[tomekzaw]

Description

This PR improves the implementation of ShadowTree cloning algorithm in NativeReanimatedModule::performOperations.

Previously, ShadowNode::cloneTree was called for each update, so effectively the root node was cloned $n$ times.

In this PR I've proposed an algorithm for solving this task more optimally. The main idea is that unsealed ShadowNodes can be still updated. In particular, their children can be replaced using ShadowNode::replaceChild. Also, freshly cloned ShadowNodes are unsealed, so each ShadowNode can be cloned only once and then updated.

One important thing to mention is that replaceChild does not update yogaChild_ field in ShadowNode, so we need to invoke ShadowNode::updateYogaChildren manually. This function has $O(n)$ time complexity where $n$ denotes the number of children. In order to avoid calling updateYogaChildren multiple number of times for the same ShadowNode, the calls are batched in std::set. Since in most use-cases there is no more than ~50 props updates, I've decided to use ordered set implementation with $O(\log{n})$ time complexity of insertion in order to save memory as well as avoid the overhead of calculating hash function (as well as to keep the order of updates).

Before	After

Execution time measurements

nested view levels	chessboard size	old algorithm [μs]	new algorithm [μs]	speedup [x]
0	10x10	4008	1326	3,0
0	20x20	15962	3620	4,4
0	30x30	50287	5939	8,5
0	40x40	131410	10669	12,3
10	10x10	105792	4058	26,1
10	20x20	388404	5935	65,4
10	30x30	879948	9334	94,3
10	40x40	1598547	15477	103,3
50	10x10	524744	11750	44,7
50	20x20	2056805	17257	119,2
50	30x30	4657397	24588	189,4
50	40x40	8305191	35413	234,5

Changes

• Implemented ShadowTreeCloner for optimal cloning ShadowTree when animating layout props on Fabric
• Used ShadowTreeCloner in NativeReanimatedModule::performOperations
• Moved creation of PropsParserContext to ShadowTreeCloner

Test code and steps to reproduce

The following examples can be used to test the algorithm:

• WidthExample
• RefExample
• ChessboardExample
• NewestShadowNodesRegistryRemoveExample

Checklist

• Included code example that can be used to test this change
• Updated TS types
• Added TS types tests
• Added unit / integration tests
• Updated documentation
• Ensured that CI passes