Rectify the flag setting for uninitializedThis in the stackmaps

[ChengJin01]

The changes are to fix the issue with the flags setting intended for uninitializedThis
in the stackmaps so as to match the JVM Spec and the RI's behavior by explicitly
outputting the detailed error messages for the mismatch captured in the stackmaps.

Internal ref 147737

Signed-off-by: ChengJin01 jincheng@ca.ibm.com

[ChengJin01]

The PR was verified in internal builds & open source builds and the expected detailed message is something like:

Exception Details:
  Location:
    c.<init>(...)V @4: JBifnonnull
  Reason:
    Current frame's flags are not assignable to stack map frame's.
  Current Frame:
    bci: @4
    flags: { flagThisUninit }
    locals: { 'uninitializedThis', 'A', 'B', 'jC', integer, integer }
    stack: { 'uninitializedThis', 'A', 'B' }
  Stackmap Frame:
    bci: @11
    flags: { }
    locals: { top, top, top, 'jC', integer, integer }
    stack: { 'uninitializedThis', 'A', 'B' }
  Stackmap Table:
    full_frame(@11,{top,top,top,Object[#25],integer,integer},{uninitializedThis,Object[#182],Object[#183]})
    full_frame(@23,{top,top,top,top,top,integer},{uninitializedThis,Object[#182],Object[#183],Object[#184]})

Reviewer: @DanHeidinga
FYI: @tajila, @pshipton, @gacholio

[DanHeidinga]

Jenkins test sanity xlinux jdk17