Adopt absl::string_view in modules/audio_coding/

Bug: webrtc:13579
Change-Id: Ifec66fb6ba9724d18539de7245a358c2d13c7939
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/268547
Reviewed-by: Ivo Creusen <ivoc@webrtc.org>
Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org>
Commit-Queue: Ali Tofigh <alito@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37573}

modules/audio_coding/neteq/tools/audio_loop.h

@@ -14,6 +14,7 @@
 #include <memory>
 #include <string>
 
+#include "absl/strings/string_view.h"
 #include "api/array_view.h"
 
 namespace webrtc {
@@ -36,7 +37,7 @@ class AudioLoop {
   // greater. Otherwise, the loop length is the same as the file length.
   // The audio will be delivered in blocks of `block_length_samples`.
   // Returns false if the initialization failed, otherwise true.
-  bool Init(std::string file_name,
+  bool Init(absl::string_view file_name,
             size_t max_loop_length_samples,
             size_t block_length_samples);