Googletest export
Googletest export

Allow copying of the string in MatchAndExplain.

Otherwise, conversions from std::string_view to std::string will fail as being
explicit

PiperOrigin-RevId: 290301103

antidotcb/googletest,empiredan/googletest,google/googletest,empiredan/googletest,gianricardo/googletest,google/googletest,antidotcb/googletest,gianricardo/googletest,antidotcb/googletest,empiredan/googletest,gianricardo/googletest,google/googletest,google/googletest,antidotcb/googletest