[10] Review request: 8183246 Remove Platform::GetSystemJRE()

[Chris Bensen]

Victor,

Please review this change to remove the dead code related to acquiring the 
system JRE for a packaged app.

JIRA: https://bugs.openjdk.java.net/browse/JDK-8183246
Webrev: http://cr.openjdk.java.net/~cbensen/JDK-8183246/webrev.00/

Chris