Fix for multi-language support.

Fix for multi-language support.

* Characters common for all scripts (i.e. white spaces or zero width joiners)
  may be set a different font than the surrounding characters.
  In some languages it causes a group of characters to be shaped in different
  groups of glyphs.

Change-Id: I0605572084252f9f3e8dab76a99d89c565924986
Signed-off-by: Victor Cebollada <v.cebollada@samsung.com>