Index separator with different font breaks xhtml

[Kornel Benko]

This is for Riki I suppose.

Selecting an index like "abc ! def" works as expected at latex output and in xhtml output

1.) Selecting different flag for '!' (like noun or emph or whatever) works OK in latex but
	breaks xhtml.
2.) Removing the spaces around '!' works OK in latex but does not separate
	the subentry 'def' in xhtml

To reproduce:
a.) open new file (title 'a'),
	select Document->Settings..->Formats->Default output format: ->LyXHTML
b.) Insert->Index entry->abc ! def
c.) Insert->List/Contents/References->Index list
d.) preview (1.png)
e.) remove spaces, preview (2.png)
f.) add spaces again, change '!' to emph, preview (3.png)

In all cases the pdf output looks like 4.png

The relevant xml code for 'Index' looks so:

<div class="standard" id='magicparlabel-304'><a id='magicparlabel-308' /></div>
<div class='index section'><h2 class="section">Index</h2><ul class='main'><li class='main'>abc <em>!</em> def: <a href='#magicparlabel-308'>1</a></li></ul>
</div>

BTW, docbook5 output omits outputting the 'Index', so this is also not ready yet.

	Kornel
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