rdar://159762558 ([SwiftFoundation Public PR swiftlang#1195] [Base64] Add new encoding options) (#3418)

Signed-off-by: Tina Liu <[email protected]>
Co-authored-by: Fabian Fett <[email protected]>

Author: itingliu

Sources/FoundationEssentials/Data/Data.swift

@@ -2918,6 +2918,15 @@ extension Data {
 }
 #endif //!FOUNDATION_FRAMEWORK
 
+extension Data.Base64EncodingOptions {
+    /// Use the base64url alphabet to encode the data
+    @available(FoundationPreview 6.3, *)
+    public static let base64URLAlphabet = Self(rawValue: 1 << 6)
+
+    /// Omit the `=` padding characters in the end of the base64 encoded result
+    @available(FoundationPreview 6.3, *)
+    public static let omitPaddingCharacter = Self(rawValue: 1 << 7)
+}
 
 @available(macOS 10.10, iOS 8.0, watchOS 2.0, tvOS 9.0, *)
 extension Data : CustomStringConvertible, CustomDebugStringConvertible, CustomReflectable {