patch 7.4.1892

Problem:    balloon eval only gets the window number, not the ID.
Solution:   Add v:beval_winid.

src/vim.h

@@ -1877,35 +1877,36 @@ typedef int sock_T;
 #define VV_FCS_CHOICE	38
 #define VV_BEVAL_BUFNR	39
 #define VV_BEVAL_WINNR	40
-#define VV_BEVAL_LNUM	41
-#define VV_BEVAL_COL	42
-#define VV_BEVAL_TEXT	43
-#define VV_SCROLLSTART	44
-#define VV_SWAPNAME	45
-#define VV_SWAPCHOICE	46
-#define VV_SWAPCOMMAND	47
-#define VV_CHAR		48
-#define VV_MOUSE_WIN	49
-#define VV_MOUSE_LNUM   50
-#define VV_MOUSE_COL	51
-#define VV_OP		52
-#define VV_SEARCHFORWARD 53
-#define VV_HLSEARCH	54
-#define VV_OLDFILES	55
-#define VV_WINDOWID	56
-#define VV_PROGPATH	57
-#define VV_COMPLETED_ITEM 58
-#define VV_OPTION_NEW   59
-#define VV_OPTION_OLD   60
-#define VV_OPTION_TYPE  61
-#define VV_ERRORS	62
-#define VV_FALSE	63
-#define VV_TRUE		64
-#define VV_NULL		65
-#define VV_NONE		66
-#define VV_VIM_DID_ENTER 67
-#define VV_TESTING	68
-#define VV_LEN		69	/* number of v: vars */
+#define VV_BEVAL_WINID	41
+#define VV_BEVAL_LNUM	42
+#define VV_BEVAL_COL	43
+#define VV_BEVAL_TEXT	44
+#define VV_SCROLLSTART	45
+#define VV_SWAPNAME	46
+#define VV_SWAPCHOICE	47
+#define VV_SWAPCOMMAND	48
+#define VV_CHAR		49
+#define VV_MOUSE_WIN	50
+#define VV_MOUSE_LNUM   51
+#define VV_MOUSE_COL	52
+#define VV_OP		53
+#define VV_SEARCHFORWARD 54
+#define VV_HLSEARCH	55
+#define VV_OLDFILES	56
+#define VV_WINDOWID	57
+#define VV_PROGPATH	58
+#define VV_COMPLETED_ITEM 59
+#define VV_OPTION_NEW   60
+#define VV_OPTION_OLD   61
+#define VV_OPTION_TYPE  62
+#define VV_ERRORS	63
+#define VV_FALSE	64
+#define VV_TRUE		65
+#define VV_NULL		66
+#define VV_NONE		67
+#define VV_VIM_DID_ENTER 68
+#define VV_TESTING	69
+#define VV_LEN		70	/* number of v: vars */
 
 /* used for v_number in VAR_SPECIAL */
 #define VVAL_FALSE	0L