Fix const correctness.

Bug: b/238157120
Change-Id: I2887b5be48d841c9ff915d669fb623b77f1e21d1
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/270481
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37679}
diff --git a/rtc_base/logging.h b/rtc_base/logging.h
index 9aa2bf2..aa530e7 100644
--- a/rtc_base/logging.h
+++ b/rtc_base/logging.h
@@ -111,12 +111,12 @@
 // the most flexible way.
 class LogLineRef {
  public:
-  absl::string_view message() { return message_; }
-  absl::string_view filename() { return filename_; };
-  int line() { return line_; };
-  absl::optional<PlatformThreadId> thread_id() { return thread_id_; };
-  webrtc::Timestamp timestamp() { return timestamp_; };
-  absl::string_view tag() const { return tag_; };
+  absl::string_view message() const { return message_; }
+  absl::string_view filename() const { return filename_; }
+  int line() const { return line_; }
+  absl::optional<PlatformThreadId> thread_id() const { return thread_id_; }
+  webrtc::Timestamp timestamp() const { return timestamp_; }
+  absl::string_view tag() const { return tag_; }
   LoggingSeverity severity() const { return severity_; }
 
   std::string DefaultLogLine() const;