Add RetainedRef uses where needed.

content/browser/media/capture/web_contents_audio_muter.cc

Index: content/browser/media/capture/web_contents_audio_muter.cc
diff --git a/content/browser/media/capture/web_contents_audio_muter.cc b/content/browser/media/capture/web_contents_audio_muter.cc
index 82a03fa5cf222f1af26d927de9f3ad42355d89ae..7423498b6d879b376084c18f9b7eceb0b9f0296c 100644
--- a/content/browser/media/capture/web_contents_audio_muter.cc
+++ b/content/browser/media/capture/web_contents_audio_muter.cc
@@ -133,11 +133,10 @@ void WebContentsAudioMuter::StartMuting() {
     return;
   is_muting_ = true;
   BrowserThread::PostTask(
-      BrowserThread::IO,
-      FROM_HERE,
+      BrowserThread::IO, FROM_HERE,
       base::Bind(&AudioMirroringManager::StartMirroring,
                  base::Unretained(AudioMirroringManager::GetInstance()),
-                 destination_));
+                 base::RetainedRef(destination_)));
 }
 
 void WebContentsAudioMuter::StopMuting() {
@@ -146,11 +145,10 @@ void WebContentsAudioMuter::StopMuting() {
     return;
   is_muting_ = false;
   BrowserThread::PostTask(
-      BrowserThread::IO,
-      FROM_HERE,
+      BrowserThread::IO, FROM_HERE,
       base::Bind(&AudioMirroringManager::StopMirroring,
                  base::Unretained(AudioMirroringManager::GetInstance()),
-                 destination_));
+                 base::RetainedRef(destination_)));
 }
 
 }  // namespace content