Delete use of STR_CASE_CMP, replaced with absl::EqualsIgnoreCase.

Bug: webrtc:5876
Change-Id: Ica2d47ca45b8ef01a548d8dbe31dbed740a0ebda
Reviewed-on: https://webrtc-review.googlesource.com/c/106820
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Commit-Queue: Niels Moller <nisse@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25306}

api/audio_codecs/ilbc/audio_decoder_ilbc.cc

@@ -14,14 +14,14 @@
 #include <vector>
 
 #include "absl/memory/memory.h"
-#include "common_types.h"  // NOLINT(build/include)
+#include "absl/strings/match.h"
 #include "modules/audio_coding/codecs/ilbc/audio_decoder_ilbc.h"
 
 namespace webrtc {
 
 absl::optional<AudioDecoderIlbc::Config> AudioDecoderIlbc::SdpToConfig(
     const SdpAudioFormat& format) {
-  return STR_CASE_CMP(format.name.c_str(), "ILBC") == 0 &&
+  return absl::EqualsIgnoreCase(format.name, "ILBC") &&
                  format.clockrate_hz == 8000 && format.num_channels == 1
              ? absl::optional<Config>(Config())
              : absl::nullopt;