perf: cache empty VList Rc in VNode::default to avoid repeated heap allocation

[Madoshakalaka]

No description provided.

[github-actions]

Visit the preview URL for this PR (updated for commit 3aad31b):

https://yew-rs-api--pr4089-perf-vnode-default-a-byvsziqq.web.app

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[github-actions]

Benchmark - core

Yew Master

vnode           fastest       │ slowest       │ median        │ mean          │ samples │ iters
╰─ vnode_clone  2.127 ns      │ 2.438 ns      │ 2.13 ns       │ 2.139 ns      │ 100     │ 1000000000

Pull Request

vnode           fastest       │ slowest       │ median        │ mean          │ samples │ iters
╰─ vnode_clone  2.155 ns      │ 2.176 ns      │ 2.161 ns      │ 2.162 ns      │ 100     │ 1000000000

[github-actions]

Size Comparison

Details

examples	master (KB)	pull request (KB)	diff (KB)	diff (%)
async_clock	100.857	100.857	0	0.000%
boids	168.449	168.575	+0.126	+0.075%
communication_child_to_parent	94.074	94.074	0	0.000%
communication_grandchild_with_grandparent	105.915	105.915	0	0.000%
communication_grandparent_to_grandchild	102.256	102.256	0	0.000%
communication_parent_to_child	91.485	91.485	0	0.000%
contexts	105.974	105.974	0	0.000%
counter	86.797	86.797	0	0.000%
counter_functional	88.832	88.832	0	0.000%
dyn_create_destroy_apps	90.711	90.824	+0.113	+0.125%
file_upload	99.812	99.925	+0.113	+0.113%
function_delayed_input	94.814	94.814	0	0.000%
function_memory_game	173.664	173.777	+0.113	+0.065%
function_router	395.766	395.879	+0.113	+0.029%
function_todomvc	164.958	165.071	+0.113	+0.069%
futures	235.550	235.552	+0.002	+0.001%
game_of_life	105.098	105.211	+0.113	+0.108%
immutable	259.622	259.731	+0.109	+0.042%
inner_html	81.340	81.340	0	0.000%
js_callback	109.961	110.073	+0.112	+0.102%
keyed_list	180.405	180.519	+0.113	+0.063%
mount_point	84.713	84.713	0	0.000%
nested_list	113.662	113.772	+0.110	+0.097%
node_refs	92.085	92.226	+0.141	+0.153%
password_strength	1718.926	1718.926	0	0.000%
portals	93.557	93.686	+0.129	+0.138%
router	366.408	366.521	+0.113	+0.031%
suspense	113.961	114.074	+0.113	+0.099%
timer	88.942	88.942	0	0.000%
timer_functional	99.368	99.368	0	0.000%
todomvc	142.660	142.773	+0.113	+0.079%
two_apps	86.710	86.710	0	0.000%
web_worker_fib	136.456	136.569	+0.113	+0.083%
web_worker_prime	187.638	187.638	0	0.000%
webgl	83.486	83.596	+0.109	+0.131%

✅ None of the examples has changed their size significantly.

[github-actions]

Benchmark - SSR

Yew Master

Details

Benchmark	Round	Min (ms)	Max (ms)	Mean (ms)	Standard Deviation
Baseline	10	270.382	280.776	271.717	3.192
Hello World	10	461.129	470.916	464.537	2.914
Function Router	10	38950.698	39687.508	39314.329	264.126
Concurrent Task	10	1005.353	1007.025	1006.281	0.560
Many Providers	10	1025.544	1088.734	1047.524	17.698

Pull Request

Details

Benchmark	Round	Min (ms)	Max (ms)	Mean (ms)	Standard Deviation
Baseline	10	270.388	272.364	270.763	0.586
Hello World	10	445.593	456.823	448.823	3.272
Function Router	10	39097.878	39458.926	39256.082	98.197
Concurrent Task	10	1004.779	1006.893	1006.262	0.783
Many Providers	10	1028.364	1055.890	1037.511	9.872