    AddPepperBasedWidevine(key_systems_info);
  #endif  // defined(WIDEVINE_CDM_AVAILABLE)
 diff --git a/media/base/key_systems.cc b/media/base/key_systems.cc
-index 511a6ef..cd3164c 100644
+index 32fa1c7..55002bd 100644
 --- a/media/base/key_systems.cc
 +++ b/media/base/key_systems.cc
-@@ -170,6 +170,10 @@ static bool IsPotentiallySupportedKeySystem(const std::string& key_system) {
+@@ -152,6 +152,10 @@ static bool IsPotentiallySupportedKeySystem(const std::string& key_system) {
    if (IsExternalClearKey(key_system))
      return true;
  

   const char kChromecastRoot[] = "com.chromecast";
   if (IsParentKeySystemOf(kChromecastRoot, key_system))
diff --git a/media/cdm/key_system_names.cc b/media/cdm/key_system_names.cc
index f0abaf0..d0fb82f 100644
--- a/media/cdm/key_system_names.cc
+++ b/media/cdm/key_system_names.cc
@@ -9,6 +9,7 @@
 namespace media {
 
 const char kClearKey[] = "org.w3.clearkey";
+const char kPlayreadyKey[] = "com.microsoft.playready";
 const char kExternalClearKey[] = "org.chromium.externalclearkey";
 
 bool IsParentKeySystemOf(const std::string& parent_key_system,
diff --git a/media/cdm/key_system_names.h b/media/cdm/key_system_names.h
index 94c84da..193684d 100644
--- a/media/cdm/key_system_names.h
+++ b/media/cdm/key_system_names.h
@@ -16,6 +16,9 @@ namespace media {

 // External Clear Key (used for testing).
 static void AddExternalClearKey(
     std::vector<KeySystemInfo>* concrete_key_systems) {
@@ -218,7 +262,7 @@ static void AddPepperBasedWidevine(
 void AddChromeKeySystems(std::vector<KeySystemInfo>* key_systems_info) {
 #if defined(ENABLE_PEPPER_CDMS)
   AddExternalClearKey(key_systems_info);
