Implement robustness strings in requestMediaKeySystemAccess().

media/base/eme_constants.h

Index: media/base/eme_constants.h
diff --git a/media/base/eme_constants.h b/media/base/eme_constants.h
index 4462c5cc0b251686c30bb1ef99b5a716248d7710..3b5fb08c8488dd2f4c93b9b3add3b4923f550d1c 100644
--- a/media/base/eme_constants.h
+++ b/media/base/eme_constants.h
@@ -60,6 +60,7 @@ enum EmeSessionTypeSupport {
   EME_SESSION_TYPE_SUPPORTED,
 };
 
+// Used to declare support for distinctive identifier and persistent state.
 enum EmeFeatureSupport {
   // Invalid default value.
   EME_FEATURE_INVALID,
@@ -74,12 +75,45 @@ enum EmeFeatureSupport {
   EME_FEATURE_ALWAYS_ENABLED,
 };
 
+// Used to query support for distinctive identifier and persistent state.

[ddorwin, 2015/03/13 19:24:47]

Not so much to query support, but to request a specific behavior. Although, if
this is used for querying whether you can match the app's request, then this
might be accurate.

[sandersd (OOO until July 31), 2015/03/13 20:11:56]

The requests are blink::WebMediaKeySystemConfiguration::Requirement values, but
they do map 1:1 with these enum values. (ConvertRequirement() does the mapping.)

The only actual difference is that I also query things that were not directly
requested (when resolving Optional).

 enum EmeFeatureRequirement {
   EME_FEATURE_NOT_ALLOWED,
   EME_FEATURE_OPTIONAL,
   EME_FEATURE_REQUIRED,
 };
 
+enum class EmeMediaType {
+  AUDIO,
+  VIDEO,
+};
+
+// Robustness values understood by KeySystems. Each value imples all those
+// before it. (This may need to be redesigned if support for non-Widevine
+// CDMs need to be supported.)
+enum class EmeRobustness {
+  INVALID,
+  EMPTY,
+  SW_SECURE_CRYPTO,
+  SW_SECURE_DECODE,
+  HW_SECURE_CRYPTO,
+  HW_SECURE_DECODE,
+  HW_SECURE_ALL,
+};
+
+// Used to answer queries about distinctive identifier, persistent state, and
+// robustness requirements.
+enum EmeRequirementSupport {
+  // The requirement is not supported.
+  EME_REQUIREMENT_NOT_SUPPORTED,
+  // The requirement is supported if the encrypted media permission is granted.
+  EME_REQUIREMENT_SUPPORTED_WITH_PERMISSION,
+  // The requirement is supported, but the user experience may be improved if
+  // the encrypted media permission is granted.
+  EME_REQUIREMENT_SUPPORTED_PERMISSION_RECOMMENDED,
+  // The requriement is supported.
+  EME_REQUIREMENT_SUPPORTED,
+};
+
 }  // namespace media
 
 #endif  // MEDIA_BASE_EME_CONSTANTS_H_