Fix various uninitialized member variables in media code.

content/renderer/media/crypto/key_systems.cc

 // Copyright 2013 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.
 
 #include "content/renderer/media/crypto/key_systems.h"
 
 #include <string>
 
 #include "base/containers/hash_tables.h"
 #include "base/lazy_instance.h"
@@ skipping 107 matching lines @@
       bool use_aes_decryptor,
 #if defined(ENABLE_PEPPER_CDMS)
       const std::string& pepper_type,
 #endif
       SupportedCodecs supported_codecs,
       const std::string& parent_key_system);
 
   friend struct base::DefaultLazyInstanceTraits<KeySystems>;
 
   struct KeySystemProperties {
-    KeySystemProperties() : use_aes_decryptor(false) {}
+    KeySystemProperties()
+        : use_aes_decryptor(false), supported_codecs(EME_CODEC_NONE) {}
 
     bool use_aes_decryptor;
 #if defined(ENABLE_PEPPER_CDMS)
     std::string pepper_type;
 #endif
     SupportedCodecs supported_codecs;
   };
 
   typedef base::hash_map<std::string, KeySystemProperties>
       KeySystemPropertiesMap;
@@ skipping 385 matching lines @@
 CONTENT_EXPORT void AddContainerMask(const std::string& container,
                                      uint32 mask) {
   KeySystems::GetInstance().AddContainerMask(container, mask);
 }
 
 CONTENT_EXPORT void AddCodecMask(const std::string& codec, uint32 mask) {
   KeySystems::GetInstance().AddCodecMask(codec, mask);
 }
 
 }  // namespace content