Add Promises for EME (Chromium side)

ppapi/api/private/pp_content_decryptor.idl

Index: ppapi/api/private/pp_content_decryptor.idl
diff --git a/ppapi/api/private/pp_content_decryptor.idl b/ppapi/api/private/pp_content_decryptor.idl
index 16be86edbf202f02cd1a09cc5021192b01ddd854..1839d400f93267bdbdf822861c0c097b30a5913b 100644
--- a/ppapi/api/private/pp_content_decryptor.idl
+++ b/ppapi/api/private/pp_content_decryptor.idl
@@ -399,3 +399,37 @@ enum PP_DecryptorStreamType {
   PP_DECRYPTORSTREAMTYPE_AUDIO = 0,
   PP_DECRYPTORSTREAMTYPE_VIDEO = 1
 };
+
+/**
+ * <code>PP_SessionType</code> contains session type constants.
+ */
+[assert_size(4)]
+enum PP_SessionType {
+  PP_SESSIONTYPE_TEMPORARY = 0,
+  PP_SESSIONTYPE_PERSISTENT = 1
+};
+
+/**
+ * <code>PP_ExceptionCodeType</code> contains exception code constants.
+ */
+[assert_size(4)]
+enum PP_ExceptionCodeType {
+  PP_EXCEPTIONCODETYPE_NOMODIFICATIONALLOWEDERROR = 0,
+  PP_EXCEPTIONCODETYPE_NOTFOUNDERROR = 1,
+  PP_EXCEPTIONCODETYPE_NOTSUPPORTEDERROR = 2,
+  PP_EXCEPTIONCODETYPE_INVALIDSTATEERROR = 3,
+  PP_EXCEPTIONCODETYPE_SYNTAXERROR = 4,
+  PP_EXCEPTIONCODETYPE_INVALIDMODIFICATIONERROR = 5,
+  PP_EXCEPTIONCODETYPE_INVALIDACCESSERROR = 6,
+  PP_EXCEPTIONCODETYPE_SECURITYERROR = 7,
+  PP_EXCEPTIONCODETYPE_ABORTERROR = 8,
+  PP_EXCEPTIONCODETYPE_QUOTAEXCEEDEDERROR = 9,
+  PP_EXCEPTIONCODETYPE_TIMEOUTERROR = 10,
+  PP_EXCEPTIONCODETYPE_UNKNOWNERROR = 11,
+  PP_EXCEPTIONCODETYPE_DATAERROR = 12,
+  PP_EXCEPTIONCODETYPE_VERSIONERROR = 13,
+  PP_EXCEPTIONCODETYPE_NOTREADABLEERROR = 14,
+  PP_EXCEPTIONCODETYPE_OPERATIONERROR = 15,
+  PP_EXCEPTIONCODETYPE_CLIENTERROR = 16,
+  PP_EXCEPTIONCODETYPE_OUTPUTERROR = 17
+};