[lldb][NFCI] Remove use of ConstString from IOHandler

None of these need to be in the ConstString StringPool. For the most
part they are constant strings and do not require fast comparisons.

I did change IOHandlerDelegateMultiline slightly -- specifically, the
`m_end_line` member always has a `\n` at the end of it now. This was so
that `IOHandlerGetControlSequence` can always return a StringRef. This
did require a slight change to `IOHandlerIsInputComplete` where we must
drop the newline before comparing it against the input parameter.

Differential Revision: https://reviews.llvm.org/D151597

1 files changed, 4 insertions, 3 deletions

diff --git a/lldb/source/Plugins/ScriptInterpreter/Python/ScriptInterpreterPythonImpl.h b/lldb/source/Plugins/ScriptInterpreter/Python/ScriptInterpreterPythonImpl.h
index b810bdb..fe75f69 100644
--- a/lldb/source/Plugins/ScriptInterpreter/Python/ScriptInterpreterPythonImpl.h
+++ b/lldb/source/Plugins/ScriptInterpreter/Python/ScriptInterpreterPythonImpl.h
@@ -434,10 +434,11 @@ public:
 
   ~IOHandlerPythonInterpreter() override = default;
 
-  ConstString GetControlSequence(char ch) override {
+  llvm::StringRef GetControlSequence(char ch) override {
+    static constexpr llvm::StringLiteral control_sequence("quit()\n");
     if (ch == 'd')
-      return ConstString("quit()\n");
-    return ConstString();
+      return control_sequence;
+    return {};
   }
 
   void Run() override {