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.

data/skeletons/lalr1.java

@@ -17,8 +17,7 @@
 
 m4_include(b4_skeletonsdir/[java.m4])
 
-b4_defines_if([b4_complain([%s: %%defines does not make sense in Java],
-              [b4_skeleton])])
+b4_defines_if([b4_complain([%defines does not make sense in Java])])
 
 # We do not depend on %debug in Java, but pacify warnings about
 # non-used flags.
@@ -26,9 +25,8 @@ b4_parse_trace_if([0], [0])
 
 m4_define([b4_symbol_no_destructor_assert],
 [b4_symbol_if([$1], [has_destructor],
-              [b4_complain([%s: %s: %%destructor does not make sense in Java],
-                        [b4_skeleton],
-                        [b4_symbol_action_location([$1], [destructor])])])])
+              [b4_complain_at(m4_unquote(b4_symbol([$1], [destructor_loc])),
+                              [%destructor does not make sense in Java])])])
 b4_symbol_foreach([b4_symbol_no_destructor_assert])
 
 # Setup some macros for api.push-pull.