[SVG] RenderSVGResourceMarker::layout() should not invalidate dependents

r160730 updated the resource-dependent client invalidation logic to
occur at mutation time, but it missed the layout() override in
RenderSVGResourceMarker - which is still invoking
removeAllClientsFromCache() and may leave nodes in an invalide state at
the end of layout.

The CL aligns RenderSVGResourceMarker's layout() implementation with
the other SVG resources (note that SVGMarkerElement's attribute listener
is already handling the invalidation).

BUG=338461
R=pdr@chromium.org,schenney@chromium.org

Review URL: https://codereview.chromium.org/147903003

git-svn-id: svn://svn.chromium.org/blink/trunk@165901 bbb929c8-8fbe-4397-9dbb-9b2b20218538
[CSS Shapes] Support inset parsing

In this patch I added support for inset shape parsing for CSS Shapes. Inset is defined
by CSS Shapes Level 1 (http://dev.w3.org/csswg/css-shapes-1/#supported-basic-shapes).
Inset is going to be used by shape-outside, and eventually by shape-inside.

Review URL: https://codereview.chromium.org/107513002

git-svn-id: svn://svn.chromium.org/blink/trunk@165902 bbb929c8-8fbe-4397-9dbb-9b2b20218538