LSC: Add std:: qualifications to all references to std::string and std::basic_string.
Adding these qualifications will make google3 C++ more portable, allow the global using std::string declarations in the google3 copy of the C++ standard library to be deleted, and bring google3 C++ in line with how the rest of the world uses C++. This completes the work started in go/lsc-add-std and go/std-type-qualification.
LSC documentation: go/lsc-std-string
Tested:
TAP --sample ran all affected tests and none failed
http://test/OCL:296724778:BASE:296722867:1582463671875:a3d40632
PiperOrigin-RevId: 296881080
Change-Id: I8d28fc887055e4cc2bde0608d3beb832d6eb5698
9 files changed
