Made some changes as requested in the PR

notebook/static/notebook/js/codecell.js

@@ -178,7 +178,7 @@ define([
             cell: this, 
             notebook: this.notebook});
         inner_cell.append(this.celltoolbar.element);
-        var input_area = $('<div/>').addClass('input_area').attr("aria-label", "Edit code here");
+        var input_area = $('<div/>').addClass('input_area').attr("aria-label", i18n.msg._("Edit code here"));
         this.code_mirror = new CodeMirror(input_area.get(0), this._options.cm_config);
         // In case of bugs that put the keyboard manager into an inconsistent state,
         // ensure KM is enabled when CodeMirror is focused:

notebook/static/notebook/js/textcell.js

@@ -98,7 +98,7 @@ define([
             cell: this, 
             notebook: this.notebook});
         inner_cell.append(this.celltoolbar.element);
-        var input_area = $('<div/>').addClass('input_area').attr("aria-label", "Edit Markup Text here");;
+        var input_area = $('<div/>').addClass('input_area').attr("aria-label", i18n.msg._("Edit Markup Text here"));
         this.code_mirror = new CodeMirror(input_area.get(0), this._options.cm_config);
         // In case of bugs that put the keyboard manager into an inconsistent state,
         // ensure KM is enabled when CodeMirror is focused: