[8u] Approval request to backport the fix made for JDK-8129740

[Srikanth]

Please approve.

JDK9 defect: https://bugs.openjdk.java.net/browse/JDK-8129740
JDK8 backport ticket: https://bugs.openjdk.java.net/browse/JDK-8157142

(1) The original patch does not apply as is after path shuffling.

However, manual application of the two failed hunks in 
LambdaToMethod.java is straightforward
and does not call for any real change in code.

(2) The file 
test/tools/javac/lambda/T8129740/SourceToSourceTranslationTest.java
required some rewriting since the ToolBox class API is different between
JDK9 and JDK8.

Relevant tests have been run and are all green.

jdk8u webrev:

http://cr.openjdk.java.net/~sadayapalam/JDK-8157142/webrev.00/

8u specific reviewer approval here:

http://mail.openjdk.java.net/pipermail/compiler-dev/2016-May/010213.html

TIA,
Srikanth