JShell behavior question: Variable re-declaration without initializer

[Robert Field]

The current behavior of JShell is that redeclaring a variable without 
initializer does not reset the value of the variable (even though the 
value of the declaration lies) --

jshell> int x = 44
x ==> 44

jshell> int x
x ==> 0

jshell> x
x ==> 44

*Is there any reason to preserve this semantics? *

One significant effect would be that VAR_DECLARATION_SUBKIND becomes an 
executable -- Snippet.isExecutable() returns true.

One major motivation for resetting it would be that sequences of 
re-evaluated code behave consistently.

-Robert