Build with Java 8

Change-Id: I06f811fc46a606b719582c0724e8d0c89e823b37
diff --git a/tools/java_doc.defs b/tools/java_doc.defs
index 2bf27cf..583407c6 100644
--- a/tools/java_doc.defs
+++ b/tools/java_doc.defs
@@ -10,13 +10,14 @@
   ):
   # TODO(davido): Actually we shouldn't need to extract the source
   # archive, javadoc should just work with provided archive.
-  external_docs.insert(0, 'http://docs.oracle.com/javase/7/docs/api')
+  external_docs.insert(0, 'http://docs.oracle.com/javase/8/docs/api')
   genrule(
     name = name,
     cmd = ' '.join([
       'mkdir $TMP/sourcepath &&',
       'unzip $(location %s) -d $TMP/sourcepath &&' % source_jar,
       'javadoc',
+      '-Xdoclint:-missing',
       '-quiet',
       '-protected',
       '-encoding UTF-8',