[quickview] Add |canDelete| property to |files-quick-view|

In preparation for adding a delete button to the Quick View toolbar add
property |canDelete| to |files-quick-view|, which indicates whether the
file shown can be deleted or not.

In a future CL, |shouldShowDeleteButton_| will then toggle the display
of the delete button in Quick View.

Test: Tests coming in future CL.
Bug: 803259
Change-Id: I880fd7f2065c11435a16ec923abca12277b0c824
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2040502
Commit-Queue: Noel Gordon <noel@chromium.org>
Reviewed-by: Noel Gordon <noel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#739221}

ui/file_manager/file_manager/foreground/elements/files_quick_view.js

@@ -14,6 +14,12 @@ const FilesQuickView = Polymer({
     // True if there is a file task that can open the file type.
     hasTask: Boolean,
 
+    /**
+     * True if the entry shown in Quick View can be deleted.
+     * @type {boolean}
+     */
+    canDelete: Boolean,
+
     // URLs should be accessible from the <webview> since their content is
     // rendered inside the <wevbiew>. Hint: use URL.createObjectURL.
     contentUrl: String,
@@ -75,6 +81,7 @@ const FilesQuickView = Polymer({
         subtype: '',
         filePath: '',
         hasTask: false,
+        canDelete: false,
         contentUrl: '',
         videoPoster: '',
         audioArtwork: '',
@@ -148,6 +155,17 @@ const FilesQuickView = Polymer({
     return hasTask && !isModal;
   },
 
+  /**
+   * @param {boolean} canDelete
+   * @param {boolean} isModal
+   * @return {boolean}
+   *
+   * @private
+   */
+  shouldShowDeleteButton_: function(canDelete, isModal) {
+    return canDelete && !isModal;
+  },
+
   /**
    * @param {!Event} event tap event.
    *

ui/file_manager/file_manager/foreground/js/file_manager_commands.js

@@ -1047,6 +1047,20 @@ CommandHandler.COMMANDS_['delete'] = new class extends Command {
         CommandUtil.hasCapability(entries, 'canDelete');
   }
 
+  /**
+   * Returns True if entries can be deleted.
+   * @param {!Array<!Entry>} entries
+   * @param {!CommandHandlerDeps} fileManager
+   * @return {!Promise<!boolean>}
+   * @public
+   */
+  canDeleteEntries(entries, fileManager) {
+    // Question: Now that we use this as a public method, in canDeleteEntries_
+    // should we now check for the condition
+    // !entries.every(CommandUtil.shouldShowMenuItemsForEntry?
+    return Promise.resolve(this.canDeleteEntries_(entries, fileManager));
+  }
+
   /**
    * Returns true if any entry belongs to a read-only volume or is
    * forced to be read-only like MyFiles>Downloads.

ui/file_manager/file_manager/foreground/js/quick_view_controller.js

@@ -381,12 +381,15 @@ class QuickViewController {
     return Promise
         .all([
           this.metadataModel_.get([entry], ['thumbnailUrl']),
-          this.taskController_.getEntryFileTasks(entry)
+          this.taskController_.getEntryFileTasks(entry),
+          CommandHandler.getCommand('delete').canDeleteEntries(
+              [entry], this.fileManager_)
         ])
         .then(values => {
           const items = (/**@type{Array<MetadataItem>}*/ (values[0]));
           const tasks = (/**@type{!FileTasks}*/ (values[1]));
-          return this.onMetadataLoaded_(entry, items, tasks);
+          const canDelete = ((values[2]));
+          return this.onMetadataLoaded_(entry, items, tasks, canDelete);
         })
         .catch(error => {
           if (error) {
@@ -404,12 +407,19 @@ class QuickViewController {
    * @param {!FileEntry} entry
    * @param {Array<MetadataItem>} items
    * @param {!FileTasks} fileTasks
+   * @param {boolean} canDelete
    * @private
    */
-  onMetadataLoaded_(entry, items, fileTasks) {
+  onMetadataLoaded_(entry, items, fileTasks, canDelete) {
+    // Question: Now that canDelete is in the typedef of QuickViewParams,
+    // closure will complain unless I add canDelete to the params object
+    // that is returned by getQuickViewParameters. This means that I am passing
+    // canDelete into getQuickViewParameters_ unnecessarily. Is this okay, or
+    // is there another way to make it so that this does not happen?
     const tasks = fileTasks.getTaskItems();
 
-    return this.getQuickViewParameters_(entry, items, tasks).then(params => {
+    return this.getQuickViewParameters_(entry, items, tasks, canDelete)
+        .then(params => {
           if (this.quickViewModel_.getSelectedEntry() != entry) {
             return;  // Bail: there's no point drawing a stale selection.
           }
@@ -419,6 +429,7 @@ class QuickViewController {
             subtype: params.subtype || '',
             filePath: params.filePath || '',
             hasTask: params.hasTask || false,
+            canDelete: params.canDelete || false,
             contentUrl: params.contentUrl || '',
             videoPoster: params.videoPoster || '',
             audioArtwork: params.audioArtwork || '',
@@ -436,11 +447,12 @@ class QuickViewController {
    * @param {!FileEntry} entry
    * @param {Array<MetadataItem>} items
    * @param {!Array<!chrome.fileManagerPrivate.FileTask>} tasks
+   * @param {boolean} canDelete
    * @return !Promise<!QuickViewParams>
    *
    * @private
    */
-  getQuickViewParameters_(entry, items, tasks) {
+  getQuickViewParameters_(entry, items, tasks, canDelete) {
     const item = items[0];
     const typeInfo = FileType.getType(entry);
     const type = typeInfo.type;
@@ -453,6 +465,7 @@ class QuickViewController {
       subtype: typeInfo.subtype,
       filePath: label,
       hasTask: tasks.length > 0,
+      canDelete: canDelete,
     };
 
     const volumeInfo = this.volumeManager_.getVolumeInfo(entry);
@@ -639,6 +652,7 @@ QuickViewController.UNSUPPORTED_IMAGE_SUBTYPES_ = [
  *   subtype: string,
  *   filePath: string,
  *   hasTask: boolean,
+ *   canDelete: boolean,
  *   contentUrl: (string|undefined),
  *   videoPoster: (string|undefined),
  *   audioArtwork: (string|undefined),