Fixing a javadoc generator failure (#94)

Author: hiranya911

pom.xml

@@ -116,9 +116,9 @@
                             <bootclasspath>${sun.boot.class.path}</bootclasspath>
                             <additionalDependencies>
                                 <additionalDependency>
-                                    <groupId>com.google.errorprone</groupId>
-                                    <artifactId>error_prone_annotations</artifactId>
-                                    <version>2.0.15</version>
+                                    <groupId>com.google.j2objc</groupId>
+                                    <artifactId>j2objc-annotations</artifactId>
+                                    <version>1.3</version>
                                 </additionalDependency>
                             </additionalDependencies>
                             <additionalparam>
@@ -186,9 +186,9 @@
                             <bootclasspath>${sun.boot.class.path}</bootclasspath>
                             <additionalDependencies>
                                 <additionalDependency>
-                                    <groupId>com.google.errorprone</groupId>
-                                    <artifactId>error_prone_annotations</artifactId>
-                                    <version>2.0.15</version>
+                                    <groupId>com.google.j2objc</groupId>
+                                    <artifactId>j2objc-annotations</artifactId>
+                                    <version>1.3</version>
                                 </additionalDependency>
                             </additionalDependencies>
                             <additionalparam>