RFR: 8247281: migrate ObjectMonitor::_object to OopStorage

[Daniel D. Daugherty]

Hi Serguei,

Welcome back from your vacation.

When you get the chance, we need you to chime in on the following review
since there are changes that affect JVM/TI and heap dumps (HPROF output):

https://git.openjdk.java.net/jdk/pull/135

Here's the bug:

     JDK-8247281 migrate ObjectMonitor::_object to OopStorage
     https://bugs.openjdk.java.net/browse/JDK-8247281

Here's the draft CSR:

     JDK-8253121 migrate ObjectMonitor::_object to OopStorage
     https://bugs.openjdk.java.net/browse/JDK-8253121

Thanks, in advance, for your comments, questions or suggestions.

Dan