vim-patch:8.1.0648: custom operators can't act upon forced motion

Problem:    Custom operators can't act upon a forced motion. (Christian
            Wellenbrock)
Solution:   Add the forced motion to the mode() result. (Christian Brabandt,
            closes vim/vim#3490)
5976f8ff00

closes #8667
closes #9476

Christian Wellenbrock:

> For (most) built in text objects it's possible to force operation on
> them to be linewise, for example by using `dVab` (`:h o_V`,
> `motion_force`). When using custom text objects (defined as mappings
> by plugins for example), this doesn't currently work.
>
> Example:
>
>     onoremap x viw
>
> Open a file with a few lines each containing some words. With the
> cursor on any word, try:
>
> 1. `dw` (builtin) deletes some characters
> 2. `dVw` (builtin) deletes linewise
> 3. `dx` (from mapping) deletes some characters
> 4. `dVx` (from mapping) deletes some characters, but should delete
>    linewise

ref: https://github.com/wellle/targets.vim/issues/214
ref: https://gitter.im/neovim/neovim?at=5b379ff7f1664406610e7483

src/nvim/globals.h

@@ -661,11 +661,13 @@ EXTERN int* (*iconv_errno)(void);
 ///    Visual_mode:    When State is NORMAL or INSERT.
 ///    finish_op  :    When State is NORMAL, after typing the operator and
 ///                    before typing the motion command.
+///    motion_force:   Last motion_force from do_pending_operator()
 EXTERN int State INIT(= NORMAL);        // This is the current state of the
                                         // command interpreter.
 
 EXTERN bool finish_op INIT(= false);    // true while an operator is pending
 EXTERN long opcount INIT(= 0);          // count for pending operator
+EXTERN int motion_force INIT(=0);       // motion force for pending operator
 
 // Ex Mode (Q) state
 EXTERN int exmode_active INIT(= 0);     // Zero, EXMODE_NORMAL or EXMODE_VIM.