[lldb][NFC] Delete unused function Breakpoint::GetEventIdentifier

[bulbazord]

Summary

This is unused

lldb/include/lldb/Breakpoint/Breakpoint.h

 /// location's condition. But if the breakpoint condition says "continue",
 /// then we will check the location for whether to actually stop or not. One
 /// subtle point worth observing here is that you don't actually stop at a
 /// Breakpoint, you always stop at one of its locations.  So the "should stop"
 /// tests are done by the location, not by the breakpoint.
 class Breakpoint : public std::enable_shared_from_this<Breakpoint>,
                    public Stoppoint {
 public:
-  static ConstString GetEventIdentifier();
   static const char *
       BreakpointEventTypeAsCString(lldb::BreakpointEventType type);
 
   /// An enum specifying the match style for breakpoint settings.  At present
   /// only used for function name style breakpoints.
   enum MatchType { Exact, Regexp, Glob };
 
 private:

lldb/source/Breakpoint/Breakpoint.cpp

 #include "lldb/Utility/StreamString.h"
 
 #include <memory>
 
 using namespace lldb;
 using namespace lldb_private;
 using namespace llvm;
 
-ConstString Breakpoint::GetEventIdentifier() {
-  static ConstString g_identifier("event-identifier.breakpoint.changed");
-  return g_identifier;
-}
-
 const char *Breakpoint::g_option_names[static_cast<uint32_t>(
     Breakpoint::OptionNames::LastOptionName)]{"Names", "Hardware"};
 
 // Breakpoint constructor
 Breakpoint::Breakpoint(Target &target, SearchFilterSP &filter_sp,
                        BreakpointResolverSP &resolver_sp, bool hardware,
                        bool resolve_indirect_symbols)
     : m_being_created(true), m_hardware(hardware), m_target(target),