Remove deprecated APIs.

lib/src/sha1.dart

Index: lib/src/sha1.dart
diff --git a/lib/src/sha1.dart b/lib/src/sha1.dart
index 9bb641154b7308fea231a4f4994ca9c0f543cd17..04107619eab0f250abb6756a45a4585f0e86ab97 100644
--- a/lib/src/sha1.dart
+++ b/lib/src/sha1.dart
@@ -25,22 +25,10 @@ class Sha1 extends Hash {
 
   Sha1._();
 
-  Sha1 newInstance() => new Sha1._();
-
   ByteConversionSink startChunkedConversion(Sink<Digest> sink) =>
       new ByteConversionSink.from(new _Sha1Sink(sink));
 }
 
-/// This class is deprecated.
-///
-/// Use [sha1] instead.
-@Deprecated("Will be removed in crypto 1.0.0.")
-class SHA1 extends Sha1 {
-  SHA1() : super._();
-
-  SHA1 newInstance() => new SHA1();
-}
-
 /// The concrete implementation of [Sha1].
 ///
 /// This is separate so that it can extend [HashBase] without leaking additional