Implement preserveAspectRatio=none for SVG images

      Previously, preserveAspectRatio=none had no effect on SVG images. This change fixes this so
we follow the special handling of preserveAspectRatio on images as defined in the spec:
    http://www.w3.org/TR/SVG/single-page.html, 7.8 The ���preserveAspectRatio��� attribute.

Images that depend on a container size (such as SVG images) require a call to
setContainerSizeForRenderer(...) to set this size. By passing the image's intrinsic size
as the container size, the non-uniform scaling defined in the spec will be achieved.

BUG=173360

Review URL: https://chromiumcodereview.appspot.com/14964004

git-svn-id: svn://svn.chromium.org/blink/trunk@149936 bbb929c8-8fbe-4397-9dbb-9b2b20218538