[lldb][nfc] Move broadcaster class strings away from ConstString (#89690)

These are hardcoded strings that are already present in the data section
of the binary, no need to immediately place them in the ConstString
StringPools. Lots of code still calls `GetBroadcasterClass` and places
the return value into a ConstString. Changing that would be a good
follow-up.

Additionally, calls to these functions are still wrapped in ConstStrings
at the SBAPI layer. This is because we must guarantee the lifetime of
all strings handed out publicly.

lldb/source/API/SBCommandInterpreter.cpp

@@ -512,7 +512,8 @@ SBBroadcaster SBCommandInterpreter::GetBroadcaster() {
 const char *SBCommandInterpreter::GetBroadcasterClass() {
   LLDB_INSTRUMENT();
 
-  return CommandInterpreter::GetStaticBroadcasterClass().AsCString();
+  return ConstString(CommandInterpreter::GetStaticBroadcasterClass())
+      .AsCString();
 }
 
 const char *SBCommandInterpreter::GetArgumentTypeAsCString(

lldb/source/API/SBCommunication.cpp

@@ -170,5 +170,6 @@ SBBroadcaster SBCommunication::GetBroadcaster() {
 const char *SBCommunication::GetBroadcasterClass() {
   LLDB_INSTRUMENT();
 
-  return ThreadedCommunication::GetStaticBroadcasterClass().AsCString();
+  return ConstString(ThreadedCommunication::GetStaticBroadcasterClass())
+      .AsCString();
 }

lldb/source/API/SBDebugger.cpp

@@ -112,7 +112,7 @@ SBDebugger &SBDebugger::operator=(const SBDebugger &rhs) {
 const char *SBDebugger::GetBroadcasterClass() {
   LLDB_INSTRUMENT();
 
-  return Debugger::GetStaticBroadcasterClass().AsCString();
+  return ConstString(Debugger::GetStaticBroadcasterClass()).AsCString();
 }
 
 const char *SBDebugger::GetProgressFromEvent(const lldb::SBEvent &event,

lldb/source/API/SBEvent.cpp

@@ -95,7 +95,8 @@ const char *SBEvent::GetBroadcasterClass() const {
 
   const Event *lldb_event = get();
   if (lldb_event)
-    return lldb_event->GetBroadcaster()->GetBroadcasterClass().AsCString();
+    return ConstString(lldb_event->GetBroadcaster()->GetBroadcasterClass())
+        .AsCString();
   else
     return "unknown class";
 }

lldb/source/API/SBProcess.cpp

@@ -77,7 +77,7 @@ SBProcess::~SBProcess() = default;
 const char *SBProcess::GetBroadcasterClassName() {
   LLDB_INSTRUMENT();
 
-  return Process::GetStaticBroadcasterClass().AsCString();
+  return ConstString(Process::GetStaticBroadcasterClass()).AsCString();
 }
 
 const char *SBProcess::GetPluginName() {
@@ -807,7 +807,7 @@ SBBroadcaster SBProcess::GetBroadcaster() const {
 const char *SBProcess::GetBroadcasterClass() {
   LLDB_INSTRUMENT();
 
-  return Process::GetStaticBroadcasterClass().AsCString();
+  return ConstString(Process::GetStaticBroadcasterClass()).AsCString();
 }
 
 size_t SBProcess::ReadMemory(addr_t addr, void *dst, size_t dst_len,

lldb/source/API/SBTarget.cpp

@@ -147,7 +147,7 @@ SBModule SBTarget::GetModuleAtIndexFromEvent(const uint32_t idx,
 const char *SBTarget::GetBroadcasterClassName() {
   LLDB_INSTRUMENT();
 
-  return Target::GetStaticBroadcasterClass().AsCString();
+  return ConstString(Target::GetStaticBroadcasterClass()).AsCString();
 }
 
 bool SBTarget::IsValid() const {

lldb/source/API/SBThread.cpp

@@ -53,7 +53,7 @@ using namespace lldb_private;
 const char *SBThread::GetBroadcasterClassName() {
   LLDB_INSTRUMENT();
 
-  return Thread::GetStaticBroadcasterClass().AsCString();
+  return ConstString(Thread::GetStaticBroadcasterClass()).AsCString();
 }
 
 // Constructors