tree 96d877bc1bd33c0dc859cb659c8e80a63a6a38f7
parent e89e100a2c89babfd1fadf6fcde9ce9125f68bb9
author fs <fs@opera.com> 1461666880 -0700
committer Commit bot <commit-bot@chromium.org> 1461666968 +0000

Don't force layout of descendants of SVG containers needing self-layout

There isn't much "layout" required for a generic SVG container - it is
sensitive to changes to its descendants and any impact a filter it
itself references has. We would however always relayout the entire
subtree of a container that had been marked as needing layout.
Like he code removed by https://codereview.chromium.org/1907273002, this
remaining part of the condition is primarily a remnant of the old way of
performing paint invalidation.
This CL changes to not force layout unconditionally based on the
self-needs-layout flag, but instead relies on the scale-factor-changed
flag (and of course specific marking of descendants) to handle this job.
To achieve this, rudimentary scale-factor-changed "detection" is added
to LayoutSVGRoot, as well as code to propagate this state to
descendants. LayoutSVGResourceMarker is modified in a similar fashion.
This is needed to counter-act the removal of the forced layout, since
previously this would propagate to descendants (unconditionally) by
forcing layout in both the root and containers. This effect is now
achieved (for the root) by using the scale-factor-changed signal
instead. This signal will be improved in future CLs.

BUG=603956

Review URL: https://codereview.chromium.org/1920833002

Cr-Commit-Position: refs/heads/master@{#389742}