fix rename (#2501)

- suppress spurious `rename` from `commander`
- handle `AST_SymbolCatch` correctly

bin/uglifyjs

@@ -72,6 +72,7 @@ if (!program.output && program.sourceMap && program.sourceMap.url != "inline") {
     "wrap"
 ].forEach(function(name) {
     if (name in program) {
+        if (name == "rename" && program[name]) return;
         options[name] = program[name];
     }
 });

lib/scope.js

@@ -456,6 +456,7 @@ AST_Toplevel.DEFMETHOD("find_unique_prefix", function(options) {
     this.globals.each(add_def);
     this.walk(new TreeWalker(function(node) {
         if (node instanceof AST_Scope) node.variables.each(add_def);
+        if (node instanceof AST_SymbolCatch) add_def(node.definition());
     }));
     var prefix, i = 0;
     do {
@@ -492,17 +493,19 @@ AST_Toplevel.DEFMETHOD("expand_names", function(options) {
     this.globals.each(rename);
     this.walk(new TreeWalker(function(node) {
         if (node instanceof AST_Scope) node.variables.each(rename);
+        if (node instanceof AST_SymbolCatch) rename(node.definition());
     }));
 
     function rename(def) {
         if (def.global || def.unmangleable(options)) return;
         if (member(def.name, options.reserved)) return;
-        var name = prefix + def.id;
+        var d = def.redefined();
+        def.name = d ? d.name : prefix + def.id;
         def.orig.forEach(function(sym) {
-            sym.name = name;
+            sym.name = def.name;
         });
         def.references.forEach(function(sym) {
-            sym.name = name;
+            sym.name = def.name;
         });
     }
 });