Add IsSupportedAudioConfig in MediaClient

media/base/key_systems_unittest.cc

Index: media/base/key_systems_unittest.cc
diff --git a/media/base/key_systems_unittest.cc b/media/base/key_systems_unittest.cc
index 665e68df4b30d07699ee6c2c25539671d791173a..62677fab143634708a792fa81a879d2103514104 100644
--- a/media/base/key_systems_unittest.cc
+++ b/media/base/key_systems_unittest.cc
@@ -180,6 +180,7 @@ class TestMediaClient : public MediaClient {
   void AddSupportedKeySystems(std::vector<std::unique_ptr<KeySystemProperties>>*
                                   key_systems_properties) override;
   void RecordRapporURL(const std::string& metric, const GURL& url) final;
+  bool IsSupportedAudioConfig(const media::AudioConfig& config) final;
   bool IsSupportedVideoConfig(const media::VideoConfig& config) final;
 
   // Helper function to test the case where IsKeySystemsUpdateNeeded() is true
@@ -231,6 +232,10 @@ void TestMediaClient::RecordRapporURL(const std::string& /* metric */,
   NOTIMPLEMENTED();
 }
 
+bool TestMediaClient::IsSupportedAudioConfig(const media::AudioConfig& config) {
+  return true;
+}
+
 bool TestMediaClient::IsSupportedVideoConfig(const media::VideoConfig& config) {
   return true;
 }