This patch replaces uses of StringRef::{starts,ends}with with
StringRef::{starts,ends}_with for consistency with
std::{string,string_view}::{starts,ends}_with in C++20.
I'm planning to deprecate and eventually remove
StringRef::{starts,ends}with.
As mentioned on https://discourse.llvm.org/t/issues-in-llvm-tblgen-high-parallelized-build/68037, ItaniumManglingCanonicalizer is often slow to build, resulting in a bottleneck for distributed builds while waiting for LLVMSupport to complete.
SymbolRemappingReader is the only current user of ItaniumManglingCanonicalizer, and this is only used by ProfileData and llvm-cxxmap - so I propose we move both files into the ProfileData library.
Differential Revision: https://reviews.llvm.org/D143318