Fix a "wrong side of point" error in CC Mode. Fixes bug #28850.

The cause was a scanning over a bracket pair taking us beyond the supplied
LIMIT parameter in c-forward-declarator.

* lisp/progmodes/cc-engine.el (c-forward-declarator): Add three checks (<
(point) limit) whilst dealing with tokens after the declared identifier.

* lisp/progmodes/cc-fonts.el (c-font-lock-declarators): Don't supply a LIMIT
argument to `c-forward-declarator' (twice), since we want to fontify up till
the end of a declarator, not an arbitrary jit-lock chunk end.

lisp/progmodes/cc-engine.el

@@ -8112,12 +8112,14 @@ comment at the start of cc-engine.el for more info."
 	 ;; initializing brace lists.
 	 (let (found)
 	   (while
-	       (and (progn
+	       (and (< (point) limit)
+		    (progn
 		      ;; In the next loop, we keep searching forward whilst
 		      ;; we find ":"s which aren't single colons inside C++
 		      ;; "for" statements.
 		      (while
 			  (and
+			   (< (point) limit)
 			   (setq found
 				 (c-syntactic-re-search-forward
 				  "[;:,]\\|\\s)\\|\\(=\\|\\s(\\)"
@@ -8139,7 +8141,7 @@ comment at the start of cc-engine.el for more info."
 		    (c-go-up-list-forward))
 	     (setq brackets-after-id t))
 	   (when found (backward-char))
-	   t))
+	   (<= (point) limit)))
 	(list id-start id-end brackets-after-id (match-beginning 1) decorated)
 
       (goto-char here)

lisp/progmodes/cc-fonts.el

@@ -1062,7 +1062,7 @@ casts and declarations are fontified.  Used on level 2 and higher."
     ;; The following `while' fontifies a single declarator id each time round.
     ;; It loops only when LIST is non-nil.
     (while
-	(and pos (setq decl-res (c-forward-declarator limit)))
+	(and pos (setq decl-res (c-forward-declarator)))
       (setq next-pos (point)
 	    id-start (car decl-res)
 	    id-face (if (and (eq (char-after) ?\()
@@ -1091,7 +1091,7 @@ casts and declarations are fontified.  Used on level 2 and higher."
 					       (throw 'is-function nil))
 					      ((not (eq got-type 'maybe))
 					       (throw 'is-function t)))
-					     (c-forward-declarator limit t)
+					     (c-forward-declarator nil t)
 					     (eq (char-after) ?,))
 					 (forward-char)
 					 (c-forward-syntactic-ws))