Revert "Merge branch 'charlesmchen/bluetoothAudio'"

This reverts commit 48a2005aa2, reversing
changes made to de1332479c.

// FREEBIE

Signal/src/ViewControllers/MessagesViewController.m

@@ -3148,9 +3148,7 @@ typedef enum : NSUInteger {
     OWSAssert(session.recordPermission == AVAudioSessionRecordPermissionGranted);
 
     NSError *error;
-    [session setCategory:AVAudioSessionCategoryRecord
-             withOptions:AVAudioSessionCategoryOptionAllowBluetooth
-                   error:&error];
+    [session setCategory:AVAudioSessionCategoryRecord error:&error];
     if (error) {
         DDLogError(@"%@ Couldn't configure audio session: %@", self.tag, error);
         [self cancelVoiceMemo];

Signal/src/call/CallAudioService.swift

@@ -105,8 +105,7 @@ import AVFoundation
                             options: .defaultToSpeaker)
         } else {
             setAudioSession(category: AVAudioSessionCategoryPlayAndRecord,
-                            mode: AVAudioSessionModeVoiceChat,
-                            options: [.allowBluetooth])
+                            mode: AVAudioSessionModeVoiceChat)
         }
     }
 
@@ -151,7 +150,7 @@ import AVFoundation
         } else {
             setAudioSession(category: AVAudioSessionCategoryPlayAndRecord,
                             mode: AVAudioSessionModeVoiceChat,
-                            options: [.mixWithOthers, .allowBluetooth])
+                            options: .mixWithOthers)
         }
 
         // HACK: Without this async, dialing sound only plays once. I don't really understand why. Does the audioSession
@@ -300,8 +299,6 @@ import AVFoundation
     private func setAudioSession(category: String,
                                  mode: String? = nil,
                                  options: AVAudioSessionCategoryOptions = AVAudioSessionCategoryOptions(rawValue: 0)) {
-        assert(Thread.isMainThread)
-
         do {
             if #available(iOS 10.0, *), let mode = mode {
                 try AVAudioSession.sharedInstance().setCategory(category, mode: mode, options: options)