media: Require HW_SECURE_CODECS for other key systems on Android.

media/base/key_systems.cc

Index: media/base/key_systems.cc
diff --git a/media/base/key_systems.cc b/media/base/key_systems.cc
index 78a1904609733808d5c3db979646f899bfd61165..6c2c8c2db31312b7074a4cc816a4ce3f9fb1a765 100644
--- a/media/base/key_systems.cc
+++ b/media/base/key_systems.cc
@@ -783,8 +783,8 @@ EmeConfigRule KeySystemsImpl::GetRobustnessConfigRule(
     return EmeConfigRule::NOT_SUPPORTED;
   }
 
-  if (key_system == kWidevineKeySystem) {
 #if defined(OS_CHROMEOS)
+  if (key_system == kWidevineKeySystem) {
     // TODO(ddorwin): Remove this once we have confirmed it is not necessary.
     // See https://crbug.com/482277
     if (robustness == EmeRobustness::EMPTY)
@@ -802,11 +802,16 @@ EmeConfigRule KeySystemsImpl::GetRobustnessConfigRule(
         max_robustness == EmeRobustness::HW_SECURE_ALL) {
       return EmeConfigRule::IDENTIFIER_RECOMMENDED;
     }
+  }
 #elif defined(OS_ANDROID)
-    if (robustness > EmeRobustness::SW_SECURE_CRYPTO)
-      return EmeConfigRule::HW_SECURE_CODECS_REQUIRED;
-#endif  // defined(OS_CHROMEOS)
+  // Require hardware secure codecs for Widevine when SW_SECURE_DECODE or above
+  // is specified, or for all other key systems (excluding Clear Key).
+  if ((key_system == kWidevineKeySystem &&
+       robustness >= EmeRobustness::SW_SECURE_DECODE) ||

[xhwang, 2016/01/15 01:19:04]

I changed this to be >= which I think is more explicit.

[ddorwin, 2016/01/15 01:32:06]

Agreed.

+      !IsClearKey(key_system)) {
+    return EmeConfigRule::HW_SECURE_CODECS_REQUIRED;
   }
+#endif  // defined(OS_CHROMEOS)
 
   return EmeConfigRule::SUPPORTED;
 }