EME: Update MediaKeySystemConfiguration defaults; require non-empty capabilities

third_party/WebKit/public/platform/WebMediaKeySystemConfiguration.h

Index: third_party/WebKit/public/platform/WebMediaKeySystemConfiguration.h
diff --git a/third_party/WebKit/public/platform/WebMediaKeySystemConfiguration.h b/third_party/WebKit/public/platform/WebMediaKeySystemConfiguration.h
index 7f69ae6105ae01e5c9144d6d2623ebd4a854e3a8..25660b2129d9bf0a1be4c1a0f2a62a90cf606358 100644
--- a/third_party/WebKit/public/platform/WebMediaKeySystemConfiguration.h
+++ b/third_party/WebKit/public/platform/WebMediaKeySystemConfiguration.h
@@ -18,28 +18,13 @@ struct WebMediaKeySystemConfiguration {
     NotAllowed,
   };
 
-  // As MediaKeySystemConfiguration is a dictionary, some members may be
-  // not-present. Because requestMediaKeySystemAccess() distinguishes empty
-  // from not-present, we require a presence flag for each member.
-  bool hasInitDataTypes = false;
+  WebString label;
   WebVector<WebEncryptedMediaInitDataType> initDataTypes;
-
-  bool hasAudioCapabilities = false;
   WebVector<WebMediaKeySystemMediaCapability> audioCapabilities;
-
-  bool hasVideoCapabilities = false;
   WebVector<WebMediaKeySystemMediaCapability> videoCapabilities;
-
-  // |distinctiveIdentifier| and |persistentState| are always present because
-  // they have default values.
   Requirement distinctiveIdentifier = Requirement::Optional;
   Requirement persistentState = Requirement::Optional;
-
-  bool hasSessionTypes = false;
   WebVector<WebEncryptedMediaSessionType> sessionTypes;
-
-  // |label| may be not-present, but we use a null string to represent that.
-  WebString label;
 };
 
 }  // namespace blink