bug#36644: Git log search

[Robert Pluim]

>>>>> On Thu, 18 Jul 2019 21:02:48 +0300, Dmitry Gutov <dgutov@yandex.ru> said:

    Dmitry> We can't really use this approach. VC is a high level
    Dmitry> abstraction, so we try to define the semantics well.

What's wrong with the semantics of 'this string is passed to the
backend as-is'? Iʼm really struggling to understand where the
motivation is coming from to escape characters in the search string,
given that each backend can have completely different regexp support.

Robert