java: use full locations for diagnostics about destructors

Currently we use the syncline to report errors about a symbol's
destructor/printer.  This is not accurate (only file and line), and
this is incorrect: the file name is double quotes (a recent change,
needed to make sure we escape properly double quotes in it).  And
worst of all: with --no-line, b4_syncline expands to nothing.

Rather, push the locations into the backend, and use them.

* src/muscle-tab.h, src/muscle-tab.c (muscle_location_grow): Make it
public.
* src/output.c (prepare_symbol_definitions): Use it to pubish the
location of the printer and destructor.
* data/skeletons/lalr1.java: Use complain_at instead of complain.
* tests/java.at (Java invalid directives): Adjust expectations.
* data/skeletons/bison.m4 (b4_symbol_action_location): Remove.
We should not use b4_syncline this way.

src/muscle-tab.c

@@ -282,11 +282,7 @@ muscle_boundary_grow (char const *key, boundary bound)
 }
 
 
-/* In the format '[[file_name:line.column]], [[file_name:line.column]]',
-   append LOC to MUSCLE.  Use digraphs for special characters in each
-   file name.  */
-
-static void
+void
 muscle_location_grow (char const *key, location loc)
 {
   muscle_boundary_grow (key, loc.start);

src/muscle-tab.h

@@ -119,6 +119,11 @@ void muscle_pair_list_grow (const char *muscle,
 void muscle_user_name_list_grow (char const *key, char const *user_name,
                                  location loc);
 
+/* In the format '[[file_name:line.column]], [[file_name:line.column]]',
+   append LOC to MUSCLE.  Use digraphs for special characters in each
+   file name.  */
+void muscle_location_grow (char const *key, location loc);
+
 /* Indicates whether a variable's value was specified with -D/--define, with
    -F/--force-define, or in the grammar file.  */
 typedef enum {

src/output.c

@@ -478,6 +478,9 @@ prepare_symbol_definitions (void)
               SET_KEY2 (pname, "line");
               MUSCLE_INSERT_INT (key, p->location.start.line);
 
+              SET_KEY2 (pname, "loc");
+              muscle_location_grow (key, p->location);
+
               SET_KEY (pname);
               MUSCLE_INSERT_STRING_RAW (key, p->code);
             }