Modify ROMClass packing to normalize more

When ROM classes are packed to be sent to the JITServer, we now
perform two additional transformations, in addition to the existing
string inlining:

1. The return bytecodes in the ROM class are fixed up if the class is
   not shared.
2. Any inlined debug info is stripped from the ROM class

Both of these are necessary to ensure that the packed representations of
shared and non-shared versions of the same ROM class are identical.

Signed-off-by: Christian Despres <despresc@ibm.com>

runtime/bcutil/ROMClassWriter.cpp

@@ -1245,6 +1245,7 @@ ROMClassWriter::writeMethods(Cursor *cursor, Cursor *lineNumberCursor, Cursor *v
 	 *  - allSlotsInROMMethodsSectionDo() in util/romclasswalk.c
 	 *  - dbgNextROMMethod() in dbgext/j9dbgext.c
 	 *  - createBreakpointedMethod() in jvmti/jvmtiHelpers.cpp
+	 *  - JITServerHelpers::packROMClass() in compiler/control/JITServerHelpers.cpp
 	 * All the above are involved in walking or walking over ROMMethods.
 	 *
 	 */