Remove some untoward dump statements that snuck into the last commit.

common/content/dactyl.js

@@ -372,7 +372,6 @@ const Dactyl = Module("dactyl", {
 
     focus: function focus(elem, flags) {
         flags = flags || services.focus.FLAG_BYMOUSE;
-        util.dumpStack();
         try {
             if (elem instanceof Document)
                 elem = elem.defaultView;

common/content/modes.js

@@ -286,7 +286,6 @@ const Modes = Module("modes", {
     },
 
     push: function push(mainMode, extendedMode, params) {
-        util.dumpStack();
         this.set(mainMode, extendedMode, params, { push: this.topOfStack });
     },