Fix cross-site popups to inherit their opener's sandbox flags even when popup opener is not set.

Fix cross-site popups to inherit their opener's sandbox flags even when popup opener is not set.

When a cross-process popup is opened from a sandboxed frame, and the
popup doesn't have window.opener set (e.g., due to rel=noopener), the
popup didn't inherit the opener frame's sandbox flags properly.
This CL fixes this case to work: we already pass the right sandbox
flags to be inherited in frame replication state, and they are also
correctly applied on the browser process side, so there's no need to
check for a non-null opener on the renderer side.

BUG=576204
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_site_isolation
TBR=creis@chromium.org

Review URL: https://codereview.chromium.org/1868823002

Cr-Commit-Position: refs/heads/master@{#386492}
(cherry picked from commit f5fb5193353e4d19ff45ad2c8baac9196086333d)

Committed: https://chromium.googlesource.com/chromium/src/+/3a1209ed605a19c071c188c564c5b6802024a6eb

[alexmos, 2016-04-18 18:06:52]

Description was changed from

==========
Fix cross-site popups to inherit their opener's sandbox flags even when popup
opener is not set.

When a cross-process popup is opened from a sandboxed frame, and the
popup doesn't have window.opener set (e.g., due to rel=noopener), the
popup didn't inherit the opener frame's sandbox flags properly.
This CL fixes this case to work: we already pass the right sandbox
flags to be inherited in frame replication state, and they are also
correctly applied on the browser process side, so there's no need to
check for a non-null opener on the renderer side.

BUG=576204
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_site_isolation
TBR=creis@chromium.org

Review URL: https://codereview.chromium.org/1868823002

Cr-Commit-Position: refs/heads/master@{#386492}
(cherry picked from commit f5fb5193353e4d19ff45ad2c8baac9196086333d)
==========

to

==========
Fix cross-site popups to inherit their opener's sandbox flags even when popup
opener is not set.

When a cross-process popup is opened from a sandboxed frame, and the
popup doesn't have window.opener set (e.g., due to rel=noopener), the
popup didn't inherit the opener frame's sandbox flags properly.
This CL fixes this case to work: we already pass the right sandbox
flags to be inherited in frame replication state, and they are also
correctly applied on the browser process side, so there's no need to
check for a non-null opener on the renderer side.

BUG=576204
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_site_isolation
TBR=creis@chromium.org

Review URL: https://codereview.chromium.org/1868823002

Cr-Commit-Position: refs/heads/master@{#386492}
(cherry picked from commit f5fb5193353e4d19ff45ad2c8baac9196086333d)

Committed:
https://chromium.googlesource.com/chromium/src/+/3a1209ed605a19c071c188c564c5...
==========

[alexmos, 2016-04-18 18:06:53]

Committed patchset #1 (id:1) manually as
3a1209ed605a19c071c188c564c5b6802024a6eb.