Make C++ digit separators work. Amend the handling of single quotes generally

Single quotes, even in strings and comments, are now marked with the
"punctuation" syntax-table property, except where they are validly bounding a
character literal.  They are font locked with font-lock-warning-face except
where they are valid.  This is done in C, C++, ObjC, and Java Modes.

* lisp/progmodes/cc-defs.el (c-clear-char-property-with-value-on-char-function)
(c-clear-char-property-with-value-on-char, c-put-char-properties-on-char): New
functions/macros.

* lisp/progmodes/cc-fonts.el (c-font-lock-invalid-single-quotes): New function.
(c-basic-matchers-before): invoke c-font-lock-invalid-single-quotes.

* lisp/progmodes/cc-langs.el (c-get-state-before-change-functions): Remove
c-before-after-change-digit-quote from wherever it occurs.  Insert
c-parse-quotes-before-change into the entries for the languages where it is
needed.
(c-before-font-lock-functions): Remove c-before-after-change-digit-quote from
wherever it occurs.  Insert c-parse-quotes-after-change into the entries for
the languages which need it.
(c-has-quoted-numbers): New lang-defconst/-defvar.

* lisp/progmodes/cc-mode.el (c-before-after-change-digit-quote): Remove.
(c-maybe-quoted-number-head, c-maybe-quoted-number-tail)
(c-maybe-quoted-number): New defconsts.
(c-quoted-number-head-before-point, c-quoted-number-tail-after-point)
(c-quoted-number-straddling-point, c-parse-quotes-before-change)
(c-parse-quotes-after-change): New functions.

lisp/progmodes/cc-langs.el

@@ -474,18 +474,19 @@ so that all identifiers are recognized as words.")
   ;; The value here may be a list of functions or a single function.
   t nil
   c++ '(c-extend-region-for-CPP
-;	c-before-after-change-extend-region-for-lambda-capture ; doesn't seem needed.
 	c-before-change-check-raw-strings
 	c-before-change-check-<>-operators
 	c-depropertize-CPP
-	c-before-after-change-digit-quote
 	c-invalidate-macro-cache
-	c-truncate-bs-cache)
+	c-truncate-bs-cache
+	c-parse-quotes-before-change)
   (c objc) '(c-extend-region-for-CPP
 	     c-depropertize-CPP
 	     c-invalidate-macro-cache
-	     c-truncate-bs-cache)
-  ;; java 'c-before-change-check-<>-operators
+	     c-truncate-bs-cache
+	     c-parse-quotes-before-change)
+  java 'c-parse-quotes-before-change
+       ;; 'c-before-change-check-<>-operators
   awk 'c-awk-record-region-clear-NL)
 (c-lang-defvar c-get-state-before-change-functions
 	       (let ((fs (c-lang-const c-get-state-before-change-functions)))
@@ -515,18 +516,19 @@ parameters \(point-min) and \(point-max).")
   t '(c-depropertize-new-text
       c-change-expand-fl-region)
   (c objc) '(c-depropertize-new-text
+	     c-parse-quotes-after-change
 	     c-extend-font-lock-region-for-macros
 	     c-neutralize-syntax-in-and-mark-CPP
 	     c-change-expand-fl-region)
   c++ '(c-depropertize-new-text
+	c-parse-quotes-after-change
 	c-extend-font-lock-region-for-macros
-;	c-before-after-change-extend-region-for-lambda-capture ; doesn't seem needed.
-	c-before-after-change-digit-quote
 	c-after-change-re-mark-raw-strings
 	c-neutralize-syntax-in-and-mark-CPP
 	c-restore-<>-properties
 	c-change-expand-fl-region)
   java '(c-depropertize-new-text
+	 c-parse-quotes-after-change
 	 c-restore-<>-properties
 	 c-change-expand-fl-region)
   awk '(c-depropertize-new-text
@@ -609,6 +611,12 @@ EOL terminated statements."
   (c c++ objc) t)
 (c-lang-defvar c-has-bitfields (c-lang-const c-has-bitfields))
 
+(c-lang-defconst c-has-quoted-numbers
+  "Whether the language has numbers quoted like 4'294'967'295."
+  t nil
+  c++ t)
+(c-lang-defvar c-has-quoted-numbers (c-lang-const c-has-quoted-numbers))
+
 (c-lang-defconst c-modified-constant
   "Regexp that matches a “modified” constant literal such as \"L\\='a\\='\",
 a “long character”.  In particular, this recognizes forms of constant