All of them. The data still needs to be downloaded to be rendered.
Maybe there's some setting I'm missing, but the default android experience seems to be Chrome downloads a pdf which then is read by Google drive.
Not really the issue with PDFs. Even if they are directly rendered the problem is they have a non-responsive rendering which forces pinch zoom and scrolling to see/read things.
DDG is one example. I prefer it this way because I can choose how to view it, and not have to redownload it in case I lose the page or the cache for the file.