[8u20] Request for approval for JDK-8037385: constant pool errors with -target 1.7 and static default methods

[Dan Smith]

Please approve this backport of langtools fix JDK-8037385 from 9 to 8u20.

Bug report: https://bugs.openjdk.java.net/browse/JDK-8037385
Changeset: http://hg.openjdk.java.net/jdk9/dev/langtools/rev/f7be68b3bd2e
jdk9 reviewers: vromero, mcimadamore

—Dan