Fix margins after they were broken in 9d988924

Changes in MediaWiki core to the padding of div#content in Vector
(see 9d988924a0350228745375e074420a0e1214f7e3 ) made the toolbar in
VisualEditor's ViewPageTarget integration for Vector render incorrectly.

This adjusts the toolbar margins to match the changes in content padding.

Bug: 61224
Change-Id: Ie6b47f5d1929533669118ba51202c1fccda4a0d6
Quick fix: image size property update

This is a bit of a workaround for scalable image nodes to update the
current size rather than only the original one. This is done so the
MediaSizeWidget in the media edit dialog is fed the current dimensions
of the image even without the image being saved.

Ideally, the node's 'currentDimensions' property should be constantly
updated to current dimensions. This workaround fixes the given bug, in
which all images show the original wikitext/default size even after
being resized.

Bug: 61052
Change-Id: I902d1f51b1389f2f9b2b5c871b578ee2244a946f
Merge "Fix margins after they were broken in 9d988924" into wmf/1.23wmf13