This CL splits getIntrinsicDimensions into getMinIntrinsicWidth,
getMaxIntrinsicWidth, getMinIntrinsicHeight, and getMaxIntrinsicHeight so that
we can properly shrink-wrap the stocks app menu. This CL just contains the
refactoring. The use in stocks app will come in a later CL.

R=ianh@google.com

Review URL: https://codereview.chromium.org/1167293003