Open folder as OK action when a folder is selected in save-as dialog.

ui/file_manager/file_manager/foreground/js/dialog_action_controller.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * Controler for handling behaviors of Files.app opened as a file/folder
  * selection dialog.
  *
  * @param {DialogType} dialogType Dialog type.
  * @param {!DialogFooter} dialogFooter Dialog footer.
@@ skipping 110 matching lines @@
 
   dialogFooter.initFileTypeFilter(
       this.fileTypes_, launchParam.includeAllFiles);
   this.onFileTypeFilterChanged_();
 }
 
 /**
  * @private
  */
 DialogActionController.prototype.processOKActionForSaveDialog_ = function() {
+  var selection = this.fileSelectionHandler_.selection;
+
+  // If OK action is clicked when a directory is selected, open the directory.
+  if (selection.directoryCount === 1 && selection.fileCount === 0) {
+    this.directoryModel_.changeDirectoryEntry(selection.entries[0]);
+    return;
+  }
+
   // Save-as doesn't require a valid selection from the list, since
   // we're going to take the filename from the text input.
   var filename = this.dialogFooter_.filenameInput.value;
   if (!filename)
     throw new Error('Missing filename!');
 
   this.namingController_.validateFileNameForSaving(filename).then(
       function(url) {
         // TODO(mtomasz): Clean this up by avoiding constructing a URL
         //                via string concatenation.
@@ skipping 295 matching lines @@
 
   if (DialogType.isFolderDialog(this.dialogType_)) {
     // In SELECT_FOLDER mode, we allow to select current directory
     // when nothing is selected.
     this.dialogFooter_.okButton.disabled =
         selection.directoryCount > 1 || selection.fileCount !== 0;
     return;
   }
 
   if (this.dialogType_ === DialogType.SELECT_SAVEAS_FILE) {
-    this.dialogFooter_.okButton.disabled =
-        this.directoryModel_.isReadOnly() ||
-        !this.dialogFooter_.filenameInput.value;
+    if (selection.directoryCount === 1 && selection.fileCount === 0) {
+      this.dialogFooter_.okButton.textContent = str('OPEN_LABEL');
+      this.dialogFooter_.okButton.disabled = false;
+    } else {
+      this.dialogFooter_.okButton.textContent = str('SAVE_LABEL');
+      this.dialogFooter_.okButton.disabled =
+          this.directoryModel_.isReadOnly() ||
+          !this.dialogFooter_.filenameInput.value;
+    }
     return;
   }
 
   if (this.dialogType_ === DialogType.SELECT_OPEN_FILE) {
     this.dialogFooter_.okButton.disabled =
         selection.directoryCount !== 0 ||
         selection.fileCount !== 1 ||
         !this.fileSelectionHandler_.isAvailable();
     return;
   }
 
   if (this.dialogType_ === DialogType.SELECT_OPEN_MULTI_FILE) {
     this.dialogFooter_.okButton.disabled =
         selection.directoryCount !== 0 ||
         selection.fileCount === 0 ||
         !this.fileSelectionHandler_.isAvailable();
     return;
   }
 
   assertNotReached('Unknown dialog type.');
 };