[8u] RFR: 8177776: Create an equivalent test case for JDK9's SupplementalJapaneseEraTest

[Naoto Sato]

Hello,

Please review the changes to the following issue:

https://bugs.openjdk.java.net/browse/JDK-8177776

The proposed change is located at:

http://cr.openjdk.java.net/~naoto/8177776/webrev.00/

This is for backporting fixes for JapaneseEra related issues (8054214, 
8173423). The original fixes in JDK9 included a test case, 
SupplementalJapaneseEraTest which is intended for the system property 
testing. The above proposed fix intends to adapt that test case into 
JDK8, where calendars.properties file is used instead of the system 
property. The test is pretty much identical to JDK9's. The difference is 
to deal with the calendars.properties file and removed some 
non-applicable cases in JDK8.

Naoto