Avoid shutdown crash if audio thread is hung.

content/browser/browser_main_loop.cc

Index: content/browser/browser_main_loop.cc
diff --git a/content/browser/browser_main_loop.cc b/content/browser/browser_main_loop.cc
index ff7508f09e3faf53897896970f9de63b046f3a31..874b3ebd60413920d0ebb39c3e60d7c692b102a9 100644
--- a/content/browser/browser_main_loop.cc
+++ b/content/browser/browser_main_loop.cc
@@ -1353,7 +1353,11 @@ void BrowserMainLoop::ShutdownThreadsAndCleanUp() {
   }
   {
     TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:AudioMan");
-    audio_manager_->Shutdown();
+    if (!audio_manager_->Shutdown()) {
+      // Intentionally leak AudioManager if shutdown failed.
+      // We might run into various CHECK(s) in AudioManager destructor.
+      ignore_result(audio_manager_.release());
+    }
   }
 
   if (parts_) {