feat(core): marker fixes per review comments 🙀

- move prepend_marker() to inline
- clear the string in context_to_string()

For: #9119

Author: srl295

core/src/ldml/ldml_processor.cpp

@@ -396,6 +396,7 @@ void ldml_processor::emit_marker(km_kbp_state *state, KMX_DWORD marker_no) {
 
 size_t
 ldml_processor::context_to_string(km_kbp_state *state, std::u32string &str) {
+    str.clear();
     auto &cp      = state->context();
     size_t ctxlen = 0; // TODO-LDML: is this needed?
     // We're only interested in as much of the context as is a KM_KBP_BT_CHAR.
@@ -413,15 +414,6 @@ ldml_processor::context_to_string(km_kbp_state *state, std::u32string &str) {
     return ctxlen; // consumed the entire context buffer.
 }
 
-void ldml_processor::prepend_marker(std::u32string &str, KMX_DWORD marker) {
-  km_kbp_usv triple[] = {
-    LDML_UC_SENTINEL,
-    LDML_MARKER_CODE,
-    marker
-  };
-  str.insert(0, triple, 3);
-}
-
 
 } // namespace kbp
 } // namespace km

core/src/ldml/ldml_processor.hpp

@@ -103,7 +103,14 @@ namespace kbp {
      static size_t context_to_string(km_kbp_state *state, std::u32string &str);
 
      /** prepend the marker string in UC_SENTINEL format to the str */
-     static void prepend_marker(std::u32string &str, KMX_DWORD marker);
+     inline static void prepend_marker(std::u32string &str, KMX_DWORD marker);
   };
+
+  void
+  ldml_processor::prepend_marker(std::u32string &str, KMX_DWORD marker) {
+     km_kbp_usv triple[] = {LDML_UC_SENTINEL, LDML_MARKER_CODE, marker};
+     str.insert(0, triple, 3);
+  }
+
 } // namespace kbp
 } // namespace km