fasta tokens implement analyzer token API

pkg/analyzer/lib/src/fasta/token_utils.dart

Index: pkg/analyzer/lib/src/fasta/token_utils.dart
diff --git a/pkg/analyzer/lib/src/fasta/token_utils.dart b/pkg/analyzer/lib/src/fasta/token_utils.dart
index 1e26cbe725486b5963efe2c68343990a5b17e270..34de7a6a55d50d015c954e47756509003ab3d73f 100644
--- a/pkg/analyzer/lib/src/fasta/token_utils.dart
+++ b/pkg/analyzer/lib/src/fasta/token_utils.dart
@@ -154,7 +154,7 @@ class ToAnalyzerTokenStreamConverter {
       _beginTokenStack.removeLast();
       _endTokenStack.removeLast();
     }
-    // Synthetic end tokens use the same offset as the begin token.
+    // Synthetic end tokens have a length of zero.
     if (translatedToken is analyzer.BeginToken &&
         token is BeginGroupToken &&
         token.endGroup != null &&
@@ -236,7 +236,7 @@ Token fromAnalyzerTokenStream(analyzer.Token analyzerToken) {
     token = token.next;
     while (token != null) {
       tail.next = fromAnalyzerToken(token);
-      tail.next.previousToken = tail;
+      tail.next.previous = tail;
       tail = tail.next;
       token = token.next;
     }
@@ -248,7 +248,7 @@ Token fromAnalyzerTokenStream(analyzer.Token analyzerToken) {
     token.precedingCommentTokens =
         translateComments(analyzerToken.precedingComments);
     tokenTail.next = token;
-    tokenTail.next.previousToken = tokenTail;
+    tokenTail.next.previous = tokenTail;
     tokenTail = token;
     matchGroups(analyzerToken, token);
     return analyzerToken.next;
@@ -258,7 +258,7 @@ Token fromAnalyzerTokenStream(analyzer.Token analyzerToken) {
     // TODO(paulberry): join up begingroup/endgroup.
     if (analyzerToken.type == TokenType.EOF) {
       tokenTail.next = new SymbolToken.eof(analyzerToken.offset);
-      tokenTail.next.previousToken = tokenTail;
+      tokenTail.next.previous = tokenTail;
       tokenTail.next.precedingCommentTokens =
           translateComments(analyzerToken.precedingComments);
       tokenTail.next.next = tokenTail.next;