Adopt absl::string_view in rtc_base/log_sinks

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

This CL adds absl::string_view versions of the OnLogMessage functions in
rtc::LogSink. The const std::string& versions are kept for now since
downstream clients use subclasses of LogSink and need to be migrated
before these are removed.

Bug: webrtc:13579
Change-Id: I57bb72ad503805ff0ca16f1d7aece2d44c65cb73
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/253980
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Reviewed-by: Xavier Lepaul‎ <xalep@webrtc.org>
Owners-Override: Xavier Lepaul‎ <xalep@webrtc.org>
Commit-Queue: Ali Tofigh <alito@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#36189}

sdk/objc/api/logging/RTCCallbackLogger.mm

@@ -10,8 +10,11 @@
 
 #import "RTCCallbackLogger.h"
 
+#import "helpers/NSString+StdString.h"
+
 #include <memory>
 
+#include "absl/strings/string_view.h"
 #include "rtc_base/checks.h"
 #include "rtc_base/log_sinks.h"
 #include "rtc_base/logging.h"
@@ -21,9 +24,13 @@ class CallbackLogSink : public rtc::LogSink {
   CallbackLogSink(RTCCallbackLoggerMessageHandler callbackHandler)
       : callback_handler_(callbackHandler) {}
 
-  void OnLogMessage(const std::string &message) override {
+  void OnLogMessage(const std::string& message) override {
+    OnLogMessage(absl::string_view(message));
+  }
+
+  void OnLogMessage(absl::string_view message) override {
     if (callback_handler_) {
-      callback_handler_([NSString stringWithUTF8String:message.c_str()]);
+      callback_handler_([NSString stringForAbslStringView:message]);
     }
   }
 
@@ -38,10 +45,10 @@ class CallbackWithSeverityLogSink : public rtc::LogSink {
 
   void OnLogMessage(const std::string& message) override { RTC_DCHECK_NOTREACHED(); }
 
-  void OnLogMessage(const std::string& message, rtc::LoggingSeverity severity) override {
+  void OnLogMessage(absl::string_view message, rtc::LoggingSeverity severity) override {
     if (callback_handler_) {
       RTCLoggingSeverity loggingSeverity = NativeSeverityToObjcSeverity(severity);
-      callback_handler_([NSString stringWithUTF8String:message.c_str()], loggingSeverity);
+      callback_handler_([NSString stringForAbslStringView:message], loggingSeverity);
     }
   }
 

sdk/objc/helpers/NSString+StdString.h

@@ -12,6 +12,8 @@
 
 #include <string>
 
+#include "absl/strings/string_view.h"
+
 NS_ASSUME_NONNULL_BEGIN
 
 @interface NSString (StdString)
@@ -23,4 +25,10 @@ NS_ASSUME_NONNULL_BEGIN
 
 @end
 
+@interface NSString (AbslStringView)
+
++ (NSString *)stringForAbslStringView:(const absl::string_view)abslStringView;
+
+@end
+
 NS_ASSUME_NONNULL_END

sdk/objc/helpers/NSString+StdString.mm

@@ -10,6 +10,8 @@
 
 #import "NSString+StdString.h"
 
+#include "absl/strings/string_view.h"
+
 @implementation NSString (StdString)
 
 - (std::string)stdString {
@@ -31,3 +33,13 @@
 }
 
 @end
+
+@implementation NSString (AbslStringView)
+
++ (NSString *)stringForAbslStringView:(const absl::string_view)abslStringView {
+  return [[NSString alloc] initWithBytes:abslStringView.data()
+                                  length:abslStringView.length()
+                                encoding:NSUTF8StringEncoding];
+}
+
+@end