Export annotations from Guava

These annotations are part of guava's API, and they cannot safely be
optimized off the compile-time classpath.

This works around google/error-prone#615.

See []
H/T @cushon

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=155433554

java/google/registry/repositories.bzl

@@ -945,7 +945,8 @@ def com_google_guava():
           "http://maven.ibiblio.org/maven2/com/google/guava/guava/20.0/guava-20.0.jar",
       ],
       licenses = ["notice"],  # The Apache Software License, Version 2.0
-      deps = [
+      exports = [
+          "@com_google_code_findbugs_jsr305",
           "@com_google_errorprone_error_prone_annotations",
       ],
   )