posAtCoords returns wrong position on inline decoration

[nono1013]

1. Setup a plugin that adds inline decorations, and add code that prints value from view.posAtCoords
2. On inline decoration it returns the start or end position of dom node instead of the actual position (it works without decorations).

See https://github.com/nono1013/pm-deco-issue/blob/main/src/main.ts for example.

While debugging I found that posAtCoords goes into posFromCaret fn, where dom.nodeType == 1 since this is a span element, and isBlock will be false, and desc has no contentDom. As I understand the execution should not go into the if this is a text or a text inside inline decoration, but since !desc.contentDom will be true, the condition results in true (If I write it as if (desc.dom.nodeType == 1 && desc.node.isBlock && (desc.parent && !sawBlock || !desc.contentDOM)) { then I get correct results, though it's etirely possible that I'm misunderstanding the code, and this will result in something bad.)

[marijnh]

Attached patch should solve this.