patch 8.2.0725: Vim9: cannot call a function declared later in Vim9 s…

…cript

Problem:    Vim9: cannot call a function declared later in Vim9 script.
Solution:   Make two passes through the script file.

patch 8.2.0724: Vim9: appending to buffer/window/tab variable not tested

Problem:    Vim9: appending to buffer/window/tab variable not tested
Solution:   Add a test.

patch 8.2.0723: Vim9: nested constant expression not evaluated compil…

…e time

Problem:    Vim9: nested constant expression not evaluated compile time.
Solution:   Use compile_expr1() for parenthesis.

patch 8.2.0722: Vim9: not handling constant expression for elseif

Problem:    Vim9: not handling constant expression for elseif.
Solution:   Use postponed constants.  Delete the code for evaluating a
            constant expression.

patch 8.2.0721: Vim9: leaking memory when skipping

Problem:    Vim9: leaking memory when skipping.
Solution:   Disable skipping in generate_ppconst().

patch 8.2.0720: occasional exit when encountering an X error

Problem:    Occasional exit when encountering an X error. (Manfred Lotz)
Solution:   On an X error do not exit, do preserve files.

patch 8.2.0719: Vim9: more expressions can be evaluated at compile time

Problem:    Vim9: more expressions can be evaluated at compile time
Solution:   Recognize has('name').

patch 8.2.0718: gcc warning for returning pointer to local variable

Problem:    Gcc warning for returning pointer to local variable. (John
            Marriott)
Solution:   Return another pointer.

patch 8.2.0717: Vim9: postponed constant expressions does not scale

Problem:    Vim9: postponed constant expressions does not scale.
Solution:   Add a structure to pass around postponed constants.

patch 8.2.0716: Vim9: another memory leak

Problem:    Vim9: another memory leak.
Solution:   Clear typval when failing.