Master broken due to febd1855eb

[Daniel]

With febd1855eb ("XML: overhaul the tag-comparison operators."), I get

/src/tex2lyx/dummy_impl.cpp:102:16: error: out-of-line
       definition of 'operator==' does not match any declaration in
       'lyx::xml::StartTag'
bool StartTag::operator==(FontTag const & rhs) const { return rhs == 
*this; }
                ^~~~~~~~
/src/tex2lyx/dummy_impl.cpp:103:15: error: out-of-line
       definition of 'operator==' does not match any declaration in
       'lyx::xml::FontTag'
bool FontTag::operator==(StartTag const & tag) const { FontTag const * c...
               ^~~~~~~~

Daniel