Ruby text interferes with fulltext search

[23452gdfg]

version:7.2
os:windows

to reproduce try to search for a phrase with ruby text in any Japanese book

for example in this phrase in the book
e4d52f1d833ed56920b040ef1045fd04 (libgen)
懇々(こんこん)と諭(さと)された
懇こん々こんと諭さとされた yields result while 懇々と諭された yield no result

expected behavior:
the sane form(懇々と諭された) should be indexed not the gibberish one

one possible solution is to discard anything in the ruby tags during the indexing processes

[Kovid Goyal (kovid)]

Fixed in branch master. The fix will be in the next release. calibre is usually released every alternate Friday.