Allow a SuggestBox to be created with a ValueBoxBase<String> instead of a
TextBox.

Deprecates the getTextBox() method in favor of getValueBox().

Contributed by: seanross
Fixes issue 7571
Review at https://codereview.appspot.com/6492092/


git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@11260 8db76d5a-ed1c-0410-87a9-c151d255dfc7