Use \u{00A0} instead of   or  

Use \u{00A0} instead of   or  

Directly use the UTF-8 encoding of the 'NO-BREAK SPACE' (U+00A0) instead of
the HTML/XML entities   or   or  .

With the UTF-8 character the generated HTML is shorter and better to read.

Also change the special value for the label in HTMLForm from   to
U+00A0 but also support   for backward compability.

Bug: T154300
Change-Id: I882599ac1120789bb4e524c4394870680caca4f4