Use LogMessageWithCallbackV() for SystemLogger

So that all logger can use specified log function like Unity Log functions.

PiperOrigin-RevId: 267505161

Author: chkuang-g

app/src/log.cc

@@ -126,8 +126,8 @@ static void LogToFile(LogLevel log_level, const char* format, va_list args) {
 #endif  // FIREBASE_LOG_TO_FILE
 
 // Log a firebase message (implemented by the platform specific logger).
-static void LogMessageWithCallbackV(LogLevel log_level, const char* format,
-                                    va_list args) {
+void LogMessageWithCallbackV(LogLevel log_level, const char* format,
+                             va_list args) {
   // We create the mutex on the heap as this can be called before the C++
   // runtime is initialized on iOS.  This ensures the Mutex class is
   // constructed before we attempt to use it.  Of course, this isn't thread

app/src/log.h

@@ -55,8 +55,11 @@ void LogError(const char* format, ...);
 void LogAssert(const char* format, ...);
 // Log a firebase message (implemented by the platform specific logger).
 void LogMessageV(LogLevel log_level, const char* format, va_list args);
-// Log a firebase message via LogMessageV().
+// Log a firebase message via LogMessageWithCallbackV().
 void LogMessage(LogLevel log_level, const char* format, ...);
+// Log a firebase message through log callback.
+void LogMessageWithCallbackV(LogLevel log_level, const char* format,
+                             va_list args);
 
 // Callback which can be used to override message logging.
 typedef void (*LogCallback)(LogLevel log_level, const char* log_message,

app/src/logger.cc

@@ -86,7 +86,7 @@ LogLevel SystemLogger::GetLogLevel() const {
 
 void SystemLogger::LogMessageImplV(LogLevel log_level, const char* format,
                                    va_list args) const {
-  ::FIREBASE_NAMESPACE::LogMessageV(log_level, format, args);
+  ::FIREBASE_NAMESPACE::LogMessageWithCallbackV(log_level, format, args);
 }
 
 Logger::~Logger() {}