[New Multicolumn] Clip correctly if the "root" layer is inside the multicol container.

When the "root" layer is inside the multicol container, don't get lost and
make the clip rectangle relative to the RenderView. It needs to be relative
to the "root" layer. When compositing, the "root" layer could be the very
same as the layer being painted.

BUG=359877
R=chrishtr@chromium.org

Review URL: https://codereview.chromium.org/848163002

git-svn-id: svn://svn.chromium.org/blink/trunk@188552 bbb929c8-8fbe-4397-9dbb-9b2b20218538
4 files changed
tree: dbad097e1dd305294df337b216cbc9d63dae62ed
  1. third_party/