Open the attached test case. The image movement is not smooth as it should be. The reason for this choppy animation is the PDF is drawn into a cached ImageBuffer every time it moves. Since the whole image is cached when it is drawn for the first time. It should not recached when the destination rectangle changes.
Created attachment 326524 [details] Apple.pdf
Created attachment 326525 [details] test case
<rdar://problem/34791461>
Created attachment 326530 [details] Patch
Comment on attachment 326530 [details] Patch Attachment 326530 [details] did not pass ios-sim-ews (ios-simulator-wk2): Output: http://webkit-queues.webkit.org/results/5172646 New failing tests: http/tests/workers/service/service-worker-clear.html
Created attachment 326540 [details] Archive of layout-test-results from ews125 for ios-simulator-wk2 The attached test failures were seen while running run-webkit-tests on the ios-sim-ews. Bot: ews125 Port: ios-simulator-wk2 Platform: Mac OS X 10.12.6
Comment on attachment 326530 [details] Patch Clearing flags on attachment: 326530 Committed r224719: <https://trac.webkit.org/changeset/224719>
All reviewed patches have been landed. Closing bug.