Bump dartdoc to f0d2276e57c96717e625964ea0385a30f2237e62

This is a commit from Jan 31 - I'm doing small bumps until we catch up
to the present.

Change-Id: Ic501dd45661992edd5e87ddb58a6cf14eb7b7ef3
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/410600
Reviewed-by: Paul Berry <[email protected]>
Commit-Queue: Samuel Rawlins <[email protected]>

Author: srawlins

DEPS

@@ -130,7 +130,7 @@ vars = {
   # 'tools/rev_sdk_deps.dart' will rev pkg dependencies to their latest; put an
   # EOL comment after a dependency to instead pin at the current revision.
   "core_rev": "0b2bd3fcd7f3e082f4cc9b14c19ffa93894b85ae",
-  "dartdoc_rev": "56934b7d567d1301ae6ad79aed9fc6f3e9fd15e3",
+  "dartdoc_rev": "f0d2276e57c96717e625964ea0385a30f2237e62",
   "ecosystem_rev": "fe4979bc6466de62eaf30b2bf59a78b4bffa3c5b",
   "flute_rev": "e4ea0459a7debae5e9592c85141707b01fac86c9",
   "glob_rev": "043796be996190473b397fa2fecfa34bb91376fb",