refactor: remove unused C string ToV8() gin converter (#44500)

shell/browser/api/electron_api_web_contents.cc

@@ -1344,7 +1344,7 @@ content::KeyboardEventProcessingResult WebContents::PreHandleKeyboardEvent(
 }
 
 void WebContents::ContentsZoomChange(bool zoom_in) {
-  Emit("zoom-changed", zoom_in ? "in" : "out");
+  Emit("zoom-changed", std::string_view{zoom_in ? "in" : "out"});
 }
 
 Profile* WebContents::GetProfile() {

shell/common/gin_converters/std_converter.h

@@ -54,14 +54,6 @@ struct Converter<std::nullptr_t> {
   }
 };
 
-template <>
-struct Converter<const char*> {
-  static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, const char* val) {
-    return v8::String::NewFromUtf8(isolate, val, v8::NewStringType::kNormal)
-        .ToLocalChecked();
-  }
-};
-
 template <>
 struct Converter<char[]> {
   static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, const char* val) {