Issue 758347  has been merged into this issue.

Could ekamarad@'s https://chromium-review.googlesource.com/c/chromium/src/+/679319 also help here?

I tested this locally and with the patch in comment #5 the bug is fixed. I am marking this bug blocked on 768029 which tracks |element.scrollIntoView()| support for OOPIFs.

That being said, fixing 768029 does not necessarily mean that scrolling for find-in-page behaves exactly the same with and without --site-per-process. We might still need to address WebViewImpl::ZoomToFindInPageRect for OOPIFs. But as far as scrolling to an element inside an OOPIF goes, the patch should fix the issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/f152db88197739be6094b050d1e59ffc724dd828

commit f152db88197739be6094b050d1e59ffc724dd828
Author: Ehsan Karamad <ekaramad@chromium.org>
Date: Mon Oct 23 17:41:25 2017

Implement recursive scrolling of rect into view for OOPIFs

Functionalities such as element.scrollIntoView() API rely on recursively
scrolling LayoutBoxes until a given rectangle in view. When the LayoutObject
is that of a LocalFrameView, the scrolling is handed over to the owner
element in the parent frame. This step is currently not implemented for
OOPIFs which consequently breaks different features such as
find-in-page and element.scrollIntoView() API.

This CL adds support for recursive scroll across OOPIFs through adding
a public struct WebRemoteScrollPropteries in blink which will be passed
from a renderer process to the browser to be then forwarded to the
parent frame. The new struct along with the rectangle to be scrolled are
the missing information needed to join the scroll chain between a child
process and its parent.

The CL adds an interactive test to catch element.scrollIntoView()
regressions in OOPIFs.

Bug:  618474 ,  676037 , 734209,  768029 
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_site_isolation
Change-Id: Iff5a5b470721f1a6e3c5db5f8f1c427a52ddb31c
Reviewed-on: https://chromium-review.googlesource.com/679319
Commit-Queue: Ehsan Karamad <ekaramad@chromium.org>
Reviewed-by: Dimitri Glazkov <dglazkov@chromium.org>
Reviewed-by: Alex Moshchuk <alexmos@chromium.org>
Reviewed-by: David Bokan <bokan@chromium.org>
Reviewed-by: Ken Buchanan <kenrb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#510838}
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/content/browser/DEPS
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/content/browser/frame_host/render_frame_host_impl.cc
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/content/browser/frame_host/render_frame_host_impl.h
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/content/browser/frame_host/render_frame_proxy_host.cc
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/content/browser/frame_host/render_frame_proxy_host.h
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/content/browser/site_per_process_browsertest.cc
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/content/common/DEPS
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/content/common/frame_messages.h
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/content/renderer/render_frame_impl.cc
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/content/renderer/render_frame_impl.h
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/content/renderer/render_frame_proxy.cc
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/content/renderer/render_frame_proxy.h
[add] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/content/test/data/bounding_rect_for_frame.html
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/Source/core/exported/LocalFrameClientImpl.cpp
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/Source/core/exported/LocalFrameClientImpl.h
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/Source/core/exported/WebRemoteFrameImpl.cpp
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/Source/core/exported/WebRemoteFrameImpl.h
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/Source/core/frame/LocalFrameClient.h
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/Source/core/frame/LocalFrameView.cpp
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/Source/core/frame/LocalFrameView.h
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/Source/core/layout/LayoutBox.cpp
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/Source/core/layout/ScrollAlignment.h
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/Source/platform/BUILD.gn
[add] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/Source/platform/exported/WebRemoteScrollProperties.cpp
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/public/BUILD.gn
[add] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/public/platform/WebRemoteScrollProperties.h
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/public/web/WebFrameClient.h
[modify] https://crrev.com/f152db88197739be6094b050d1e59ffc724dd828/third_party/WebKit/public/web/WebRemoteFrame.h

Is this fixed now?  It does seem to be working in 64.0.3264.0 with --site-per-process.  (Thanks!)

While the issue might not be 100% fixed (ZoomToFindInPageRect is not implemented for OOPIFs), the repro steps in the description do not reproduce the behavior on Canary anymore. So AFA the bug description goes, I'd consider the bug fixed.

Thanks!  I'll mark it fixed then.  Perhaps you can file a followup bug for ZoomToFindInPageRect?)