Implement rect conversion utility functions in View

Add the following utility functions (similar to their
point-based counterparts):

View::ConvertRectToTarget()
View::ConvertRectToAncestor()
View::ConvertRectFromAncestor()

BUG=306182

Review URL: https://codereview.chromium.org/26884003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229711 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 229711