Make autoplay policies no longer platform dependant.

media/base/media_util.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_BASE_MEDIA_UTIL_H_
 #define MEDIA_BASE_MEDIA_UTIL_H_
 
 #include <stdint.h>
+#include <string>
 #include <vector>
 
 #include "media/base/encryption_scheme.h"
 #include "media/base/media_export.h"
 
+namespace base {
+class CommandLine;
+}
+
 namespace media {
 
 // Simply returns an empty vector. {Audio|Video}DecoderConfig are often
 // constructed with empty extra data.
 MEDIA_EXPORT std::vector<uint8_t> EmptyExtraData();
 
 // The following helper functions return new instances of EncryptionScheme that
 // indicate widely used settings.
 MEDIA_EXPORT EncryptionScheme Unencrypted();
 MEDIA_EXPORT EncryptionScheme AesCtrEncryptionScheme();
 
+// Based on a |command_line| and the current platform, returns the effective

[DaleCurtis, 2017/04/27 18:59:39]

Hmm, I didn't even know we had a media_util file, this should probably be
deleted and these moved elsewhere. Can we keep this method in media_witches?

[mlamouri (slow - plz ping), 2017/04/27 21:34:14]

I was considering having this in media_switches but happy to invoke some witches
:)

+// autoplay policy. In other words, it will take into account the default policy
+// if none is specified via the command line and options passed for testing.
+// Returns one of the possible autoplay policy switches from the
+// switches::autoplay namespace.
+MEDIA_EXPORT std::string GetEffectiveAutoplayPolicy(
+    const base::CommandLine& command_line);
+
 }  // namespace media
 
 #endif  // MEDIA_BASE_MEDIA_UTIL_H_