Remove subpixel hacks from RenderTreeAsText

RenderTreeAsText currently reports the enclosing rect of an object
rather than the more precise logical location and size.
Remove this hack and update the test expectations accordingly.

BUG=263879
R=leviw@chromium.org

Review URL: https://codereview.chromium.org/19578006

git-svn-id: svn://svn.chromium.org/blink/trunk@154918 bbb929c8-8fbe-4397-9dbb-9b2b20218538