Use doclint option -missing instead of none.

Author: ueshin

pom.xml

@@ -1186,7 +1186,7 @@
             <groupId>org.apache.maven.plugins</groupId>
             <artifactId>maven-javadoc-plugin</artifactId>
             <configuration>
-              <additionalparam>-Xdoclint:none</additionalparam>
+              <additionalparam>-Xdoclint:-missing</additionalparam>
             </configuration>
           </plugin>
         </plugins>

project/SparkBuild.scala

@@ -130,7 +130,7 @@ object SparkBuild extends PomBuild {
 
     javacOptions in (Compile, doc) ++= {
       val Array(major, minor, _) = System.getProperty("java.version").split("\\.", 3)
-      if (major.toInt >= 1 && minor.toInt >= 8) Seq("-Xdoclint:none") else Seq.empty
+      if (major.toInt >= 1 && minor.toInt >= 8) Seq("-Xdoclint:-missing") else Seq.empty
     }
   )