fix: getRootNode when composed is false and the element is the root

[pmdartus]

Details

Fix error throw in getRootNode when the component is the root of the component tree.

Does this PR introduce a breaking change?

• Yes
• No

[caridy]

this seems functional equivalent, just cosmetic changes. Can you confirm?

[davidturissini]

I think that's correct

[pmdartus]

Yes, you are right.

[caridy]

can you explain what the problem was? in which scenario?

[davidturissini]

The problem was finding the root node on an element rendered in interop. Since there is no parent VM, it was traversing to the document root. Because this isn't inside of a closed root, going to the document root seems correct.

[pmdartus]

There is already a test case for this. https://github.com/salesforce/lwc/pull/337/files#diff-2a67454c78a85e47d3e8214bb464d731R114

However, if you look at the diff, the composed was set to true instead of false, explaining why we didn't catch that before. I fixed the test.

[salesforce-best-lwc-internal]

Benchmark results

Base commit: 51adcb6 | Target commit: 729538e

lwc-engine-benchmark

table-append-1k	metric	base(51adcb6)	target(729538e)	trend
benchmark-table/append/1k	duration	145.00 (± 5.60 ms)	146.30 (± 5.10 ms)	-0.90% 👌

table-clear-1k	metric	base(51adcb6)	target(729538e)	trend
benchmark-table/clear/1k	duration	11.80 (± 0.50 ms)	11.70 (± 0.50 ms)	0.85% 👌

table-create-10k	metric	base(51adcb6)	target(729538e)	trend
benchmark-table/create/10k	duration	844.30 (± 3.70 ms)	863.40 (± 6.80 ms)	-2.26% 👎

table-create-1k	metric	base(51adcb6)	target(729538e)	trend
benchmark-table/create/1k	duration	101.70 (± 2.00 ms)	101.50 (± 2.10 ms)	0.20% 👌

table-update-10th-1k	metric	base(51adcb6)	target(729538e)	trend
benchmark-table/update-10th/1k	duration	92.50 (± 5.15 ms)	93.80 (± 4.40 ms)	-1.41% 👌

tablecmp-append-1k	metric	base(51adcb6)	target(729538e)	trend
benchmark-table-component/append/1k	duration	242.10 (± 5.20 ms)	247.30 (± 4.30 ms)	-2.15% 👎

tablecmp-clear-1k	metric	base(51adcb6)	target(729538e)	trend
benchmark-table/clear/1k	duration	33.00 (± 1.10 ms)	32.40 (± 1.40 ms)	1.82% 👌

tablecmp-create-10k	metric	base(51adcb6)	target(729538e)	trend
benchmark-table-component/create/10k	duration	1712.50 (± 6.50 ms)	1668.50 (± 11.70 ms)	2.57% 👍

tablecmp-create-1k	metric	base(51adcb6)	target(729538e)	trend
benchmark-table-component/create/1k	duration	188.70 (± 3.90 ms)	191.40 (± 3.80 ms)	-1.43% 👌

tablecmp-update-10th-1k	metric	base(51adcb6)	target(729538e)	trend
benchmark-table-component/update-10th/1k	duration	74.40 (± 5.10 ms)	73.00 (± 2.90 ms)	1.88% 👌