This patch fixes PR32896.
The problem was that modernize-use-emplace incorrectly removed changed push_back into emplace_back, removing explicit constructor call with initializer list parameter, resulting in compiler error after applying fixits.
modernize-use-emplace used to check if matched constructor had InitListExpr, but didn't check against CXXStdInitializerListExpr.
Eg.
std::vector<std::vector<int>> v; v.push_back(std::vector<int>({1})); // --> v.emplace_back({1});