Make RTCAudioSession accessible to Swift.

This is done by:
1. removing the <vector> include from RTCAudioSession+Private,
2. creating a audio_session_objc package that excludes the RTCNativeAudioSessionDelegateAdapter class.

Bug: webrtc:11237
Change-Id: I36c86542a19e3244456fd164d908563b1435de29
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/163900
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Kári Helgason <kthelgason@webrtc.org>
Reviewed-by: Chuck Hays <haysc@webrtc.org>
Reviewed-by: Henrik Andreassson <henrika@webrtc.org>
Commit-Queue: Kári Helgason <kthelgason@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#30177}

PRESUBMIT.py

@@ -521,7 +521,7 @@ def CheckPublicDepsIsNotUsed(gn_files, input_api, output_api):
   """Checks that public_deps is not used without a good reason."""
   result = []
   no_presubmit_check_re = input_api.re.compile(
-      r'# no-presubmit-check TODO\(webrtc:8603\)')
+      r'# no-presubmit-check TODO\(webrtc:\d+\)')
   error_msg = ('public_deps is not recommended in WebRTC BUILD.gn files '
                'because it doesn\'t map well to downstream build systems.\n'
                'Used in: %s (line %d).\n'

sdk/BUILD.gn

@@ -286,7 +286,37 @@ if (is_ios || is_mac) {
         libs = [ "AudioToolbox.framework" ]
       }
 
-      rtc_library("audio_objc") {
+      # This target exists to expose :audio_session_objc and
+      # :audio_session_delegate_adapter_objc for backward compatibility,
+      # and should be deprecated.
+      group("audio_objc") {
+        public_deps = [  # no-presubmit-check TODO(webrtc:11238)
+          ":audio_session_delegate_adapter_objc",
+          ":audio_session_objc",
+        ]
+      }
+
+      rtc_library("audio_session_delegate_adapter_objc") {
+        sources = [
+          "objc/components/audio/RTCNativeAudioSessionDelegateAdapter.h",
+          "objc/components/audio/RTCNativeAudioSessionDelegateAdapter.mm",
+        ]
+
+        configs += [
+          "..:common_objc",
+          ":used_from_extension",
+        ]
+
+        public_configs = [ ":common_config_objc" ]
+
+        deps = [
+          ":audio_session_objc",
+          ":audio_session_observer",
+          ":base_objc",
+        ]
+      }
+
+      rtc_library("audio_session_objc") {
         sources = [
           "objc/components/audio/RTCAudioSession+Configuration.mm",
           "objc/components/audio/RTCAudioSession+Private.h",
@@ -294,9 +324,8 @@ if (is_ios || is_mac) {
           "objc/components/audio/RTCAudioSession.mm",
           "objc/components/audio/RTCAudioSessionConfiguration.h",
           "objc/components/audio/RTCAudioSessionConfiguration.m",
-          "objc/components/audio/RTCNativeAudioSessionDelegateAdapter.h",
-          "objc/components/audio/RTCNativeAudioSessionDelegateAdapter.mm",
         ]
+
         configs += [
           "..:common_objc",
           ":used_from_extension",
@@ -307,7 +336,6 @@ if (is_ios || is_mac) {
         libs = [ "AVFoundation.framework" ]
 
         deps = [
-          ":audio_session_observer",
           ":base_objc",
           ":helpers_objc",
           "../rtc_base",
@@ -1073,7 +1101,7 @@ if (is_ios || is_mac) {
 
           deps = [
             ":audio_device",
-            ":audio_objc",
+            ":audio_session_objc",
             ":base_objc",
             ":callback_logger_objc",
             ":framework_objc",
@@ -1225,7 +1253,7 @@ if (is_ios || is_mac) {
 
         if (is_ios) {
           sources += [ "objc/unittests/RTCAudioSessionTest.mm" ]
-          deps += [ ":audio_objc" ]
+          deps += [ ":audio_session_objc" ]
         }
       }
     }

sdk/objc/components/audio/RTCAudioSession+Private.h

@@ -10,8 +10,6 @@
 
 #import "RTCAudioSession.h"
 
-#include <vector>
-
 NS_ASSUME_NONNULL_BEGIN
 
 @class RTCAudioSessionConfiguration;
@@ -77,8 +75,6 @@ NS_ASSUME_NONNULL_BEGIN
 - (NSError *)configurationErrorWithDescription:(NSString *)description;
 
 // Properties and methods for tests.
-@property(nonatomic, readonly) std::vector<__weak id<RTCAudioSessionDelegate> > delegates;
-
 - (void)notifyDidBeginInterruption;
 - (void)notifyDidEndInterruptionWithShouldResumeSession:(BOOL)shouldResumeSession;
 - (void)notifyDidChangeRouteWithReason:(AVAudioSessionRouteChangeReason)reason

sdk/objc/components/audio/RTCAudioSession.mm

@@ -12,6 +12,8 @@
 
 #import <UIKit/UIKit.h>
 
+#include <vector>
+
 #include "rtc_base/atomic_ops.h"
 #include "rtc_base/checks.h"
 #include "rtc_base/critical_section.h"
@@ -25,6 +27,10 @@ NSInteger const kRTCAudioSessionErrorLockRequired = -1;
 NSInteger const kRTCAudioSessionErrorConfiguration = -2;
 NSString * const kRTCAudioSessionOutputVolumeSelector = @"outputVolume";
 
+@interface RTCAudioSession ()
+@property(nonatomic, readonly) std::vector<__weak id<RTCAudioSessionDelegate> > delegates;
+@end
+
 // This class needs to be thread-safe because it is accessed from many threads.
 // TODO(tkchin): Consider more granular locking. We're not expecting a lot of
 // lock contention so coarse locks should be fine for now.

sdk/objc/unittests/RTCAudioSessionTest.mm

@@ -11,6 +11,8 @@
 #import <Foundation/Foundation.h>
 #import <OCMock/OCMock.h>
 
+#include <vector>
+
 #include "rtc_base/gunit.h"
 
 #import "components/audio/RTCAudioSession+Private.h"
@@ -20,6 +22,8 @@
 
 @interface RTCAudioSession (UnitTesting)
 
+@property(nonatomic, readonly) std::vector<__weak id<RTCAudioSessionDelegate> > delegates;
+
 - (instancetype)initWithAudioSession:(id)audioSession;
 
 @end