[8u20] Request for approval: 8033686 - Internal error for zero indent

[Alexander Zuev]

One more javap-related backports from jdk9.

Bug: https://bugs.openjdk.java.net/browse/JDK-8033686
Fix pushed as: 
http://hg.openjdk.java.net/jdk9/dev/langtools/rev/bd6e1d99d942
Fix applies without an issue to 
http://hg.openjdk.java.net/jdk8u/jdk8u-dev/langtools
Webrev is available at: http://cr.openjdk.java.net/~kizune/8033972/webrev.00

/Alex