Make Blockly.Flyout a goog.ui.Component.

There are _some_ hacks here with TODO comments that can be removed when Toolbox
is componentized.

TBR=neil.fraser@gmail.com
BUG=104

Review URL: https://codereview.appspot.com/7221056

git-svn-id: http://blockly.googlecode.com/svn/trunk@609 c400ca83-b69d-9dd7-9705-49c6b8615e23
Fixed wrapping style nit.

git-svn-id: http://blockly.googlecode.com/svn/trunk@610 c400ca83-b69d-9dd7-9705-49c6b8615e23