MD Settings: Prevent flash of subpage when collapsing section

MD Settings: Prevent flash of subpage when collapsing section

settings-subpage should never show its overflow.

In practice, AFAICT, its content only exceeds its boundaries during the
collapse animation when navigating back to the main page from a subpage.
The settings-section handles clipping for that collapse animation, so
we don't need "overflow: hidden" on the subpage. But when the collapse
the collapse animation finishes, we remove clipping from
settings-section.[1] The settings-subpage then becomes visible
over the rest of the page during a brief moment while it completes its
fade-out animation.

By setting a constant "overflow: hidden" on settings-subpage, we ensure
that its content does not overflow after the settings-section has collapsed
while the subpage is finishing its fade-out animation.

[1] This lets us show search bubbles outside the settings-section boundary.

BUG=716680
R=dpapad@chromium.org
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

[michaelpg, 2017-04-29 00:41:04]

Description was changed from

==========
MD Settings: Prevent flash of subpage when collapsing section

settings-subpage should never show its overflow.

In practice, AFAICT, its content only exceeds its boundaries during the
collapse animation when navigating back to the main page from a subpage.
The settings-section handles clipping for that collapse animation, so
we don't need "overflow: hidden" on the subpage. But when the collapse
the collapse animation finishes, we remove clipping from
settings-section.[1] The settings-subpage then becomes visible
over the rest of the page during a brief moment while it completes its
fade-out animataion.

By setting a constant "overflow: hidden" on settings-subpage, we ensure
that its content does not overflow after the settings-section has collapsed
while the subpage is finishing its fade-out animation.

[1] This lets us show search bubbles outside the settings-section boundary.

BUG=716680
R=dpapad@chromium.org
==========

to

==========
MD Settings: Prevent flash of subpage when collapsing section

settings-subpage should never show its overflow.

In practice, AFAICT, its content only exceeds its boundaries during the
collapse animation when navigating back to the main page from a subpage.
The settings-section handles clipping for that collapse animation, so
we don't need "overflow: hidden" on the subpage. But when the collapse
the collapse animation finishes, we remove clipping from
settings-section.[1] The settings-subpage then becomes visible
over the rest of the page during a brief moment while it completes its
fade-out animataion.

By setting a constant "overflow: hidden" on settings-subpage, we ensure
that its content does not overflow after the settings-section has collapsed
while the subpage is finishing its fade-out animation.

[1] This lets us show search bubbles outside the settings-section boundary.

BUG=716680
R=dpapad@chromium.org
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation
==========

[michaelpg, 2017-04-29 00:45:07]

Description was changed from

==========
MD Settings: Prevent flash of subpage when collapsing section

settings-subpage should never show its overflow.

In practice, AFAICT, its content only exceeds its boundaries during the
collapse animation when navigating back to the main page from a subpage.
The settings-section handles clipping for that collapse animation, so
we don't need "overflow: hidden" on the subpage. But when the collapse
the collapse animation finishes, we remove clipping from
settings-section.[1] The settings-subpage then becomes visible
over the rest of the page during a brief moment while it completes its
fade-out animataion.

By setting a constant "overflow: hidden" on settings-subpage, we ensure
that its content does not overflow after the settings-section has collapsed
while the subpage is finishing its fade-out animation.

[1] This lets us show search bubbles outside the settings-section boundary.

BUG=716680
R=dpapad@chromium.org
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation
==========

to

==========
MD Settings: Prevent flash of subpage when collapsing section

settings-subpage should never show its overflow.

In practice, AFAICT, its content only exceeds its boundaries during the
collapse animation when navigating back to the main page from a subpage.
The settings-section handles clipping for that collapse animation, so
we don't need "overflow: hidden" on the subpage. But when the collapse
the collapse animation finishes, we remove clipping from
settings-section.[1] The settings-subpage then becomes visible
over the rest of the page during a brief moment while it completes its
fade-out animation.

By setting a constant "overflow: hidden" on settings-subpage, we ensure
that its content does not overflow after the settings-section has collapsed
while the subpage is finishing its fade-out animation.

[1] This lets us show search bubbles outside the settings-section boundary.

BUG=716680
R=dpapad@chromium.org
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation
==========

[michaelpg, 2017-04-29 00:46:01]

PTAL. Further explained in crbug.com/716680.

[dpapad, 2017-05-02 20:34:09]

LGTM. I tried it locally too and could not find a way to break it. Having said
that, this fix relies on the fact that we never show a bubble within a
settings-subpage (otherwise it could get clipped).

[michaelpg, 2017-05-05 21:09:02]

On 2017/05/02 20:34:09, dpapad wrote:
> LGTM. I tried it locally too and could not find a way to break it. Having said
> that, this fix relies on the fact that we never show a bubble within a
> settings-subpage (otherwise it could get clipped).

Yeah, that's unfortunate. The primary repro case has likely been resolved with
crrev.com/2856223007/ so I'll hold off on landing this CL.