Adopt absl::string_view in function parameters under rtc_base/

This is part of a large-scale effort to increase adoption of
absl::string_view across the WebRTC code base.

This CL converts the majority of "const std::string&"s in function
parameters under rtc_base/ to absl::string_view.

Bug: webrtc:13579
Change-Id: I2b1e3776aa42326aa405f76bb324a2d233b21dca
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/254081
Reviewed-by: Niels Moller <nisse@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Xavier Lepaul‎ <xalep@webrtc.org>
Reviewed-by: Anders Lilienthal <andersc@webrtc.org>
Reviewed-by: Per Kjellander <perkj@webrtc.org>
Commit-Queue: Ali Tofigh <alito@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#36239}
diff --git a/rtc_base/ssl_stream_adapter.cc b/rtc_base/ssl_stream_adapter.cc
index b805fdc..4b60d6d 100644
--- a/rtc_base/ssl_stream_adapter.cc
+++ b/rtc_base/ssl_stream_adapter.cc
@@ -11,6 +11,7 @@
 #include "rtc_base/ssl_stream_adapter.h"
 
 #include "absl/memory/memory.h"
+#include "absl/strings/string_view.h"
 #include "rtc_base/openssl_stream_adapter.h"
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -39,7 +40,7 @@
   }
 }
 
-int SrtpCryptoSuiteFromName(const std::string& crypto_suite) {
+int SrtpCryptoSuiteFromName(absl::string_view crypto_suite) {
   if (crypto_suite == kCsAesCm128HmacSha1_32)
     return kSrtpAes128CmSha1_32;
   if (crypto_suite == kCsAesCm128HmacSha1_80)
@@ -85,7 +86,7 @@
           crypto_suite == kSrtpAeadAes128Gcm);
 }
 
-bool IsGcmCryptoSuiteName(const std::string& crypto_suite) {
+bool IsGcmCryptoSuiteName(absl::string_view crypto_suite) {
   return (crypto_suite == kCsAeadAes256Gcm || crypto_suite == kCsAeadAes128Gcm);
 }
 
@@ -98,7 +99,7 @@
   return false;
 }
 
-bool SSLStreamAdapter::ExportKeyingMaterial(const std::string& label,
+bool SSLStreamAdapter::ExportKeyingMaterial(absl::string_view label,
                                             const uint8_t* context,
                                             size_t context_len,
                                             bool use_context,
@@ -122,7 +123,7 @@
 bool SSLStreamAdapter::IsAcceptableCipher(int cipher, KeyType key_type) {
   return OpenSSLStreamAdapter::IsAcceptableCipher(cipher, key_type);
 }
-bool SSLStreamAdapter::IsAcceptableCipher(const std::string& cipher,
+bool SSLStreamAdapter::IsAcceptableCipher(absl::string_view cipher,
                                           KeyType key_type) {
   return OpenSSLStreamAdapter::IsAcceptableCipher(cipher, key_type);
 }