Request for approval for 7180906 to be fixed in jdk7u-dev/langtools

[Bhavesh Patel]

- bugs.sun.com:
    http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7180906

- The patch is the same as that in jdk 8:
    http://hg.openjdk.java.net/jdk8/tl/langtools/rev/fa85af323d97

- testing:
    - ran all the javadoc regression tests on different platforms.