Fixes #16255: DOM lib is missing Intersection Observer API on window …

[johan-gorter]

Fixes #16255

[msftclas]

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[ikatyang]

These files are not meant to be edited by hand. If you need to make modifications, the respective files should be changed within the repository's top-level src directory. Running jake LKG will then appropriately update the files in this directory. (https://github.com/Microsoft/TypeScript/tree/master/lib#readme)

-> https://github.com/Microsoft/TypeScript/tree/master/src/lib#readme

[mhegazy]

what @ikatyang said.

[johan-gorter]

I tried to understand where the change should be made and I found the TSJS-lib-generator project. But from there I do not know where I need to make the changes. Giving up.

[kitsonk]

@johan-gorter I believe it just needs to be added to the JSON structure in addedTypes.