Revert "[Reland attempt #2] Refactor DirectoryTree"

This reverts commit b7ecb7e9.

Reason for revert: ChromiumOS MSAN got flaky/failing crbug.com/899664

Original change's description:
> [Reland attempt #2] Refactor DirectoryTree
> 
> Fix flakiness by adding call to this.expanded=true in EntryListItem.
> 
> Change updateSubDirectories:
> - use arrow function and const;
> - change error callback calling style to match the same style used by
> success callback (without if).
> - change check from isFakeEntry to check for presence of the method
> that's used "createReader".
> 
> Change the sorting to be an method, so it can be customized per
> sub-class, later it will be used to sort My files to show Linux and Play
> files at the bottom.
> 
> Fix unittest that started failing because it metadataModel was null.
> 
> No changes in behaviour for users, the small change in behaviour is
> EntryListItem.updateSubDirectories now reads its children using FS API
> which isn't synchronous.
> 
> CrOS FilesApp UI Tests: ensure downloads selected and refreshed in setup
> 
> TBR: joelhockey@chromium.org
> Bug: 899664
> Change-Id: I8a93616f74cf3bf2b99851dc2452249e1353d85e
> Reviewed-on: https://chromium-review.googlesource.com/c/1306963
> Reviewed-by: Joel Hockey <joelhockey@chromium.org>
> Commit-Queue: Luciano Pacheco <lucmult@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#604069}

TBR=joelhockey@chromium.org,lucmult@chromium.org

Change-Id: Ic7903e70225a59e3eca7d581ea44202462b01dee
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 899664
Reviewed-on: https://chromium-review.googlesource.com/c/1309570Reviewed-by: Luciano Pacheco <lucmult@chromium.org>
Commit-Queue: Luciano Pacheco <lucmult@chromium.org>
Cr-Commit-Position: refs/heads/master@{#604194}

ui/file_manager/file_manager/foreground/js/directory_model.js

@@ -972,8 +972,6 @@ DirectoryModel.prototype.changeDirectoryEntry = function(
   if (dirEntry instanceof VolumeEntry)
     dirEntry = assert(dirEntry.rootEntry);
 
-  // TODO(lucmult): Remove this log once flakiness is fixed.
-  console.log('changeDirectoryEntry: ',  dirEntry.name);
   // Increment the sequence value.
   this.changeDirectorySequence_++;
   this.clearSearch_();

ui/file_manager/file_manager/foreground/js/ui/directory_tree.js

@@ -482,17 +482,6 @@ DirectoryItem.prototype.handleClick = function(e) {
   }
 };
 
-/**
- * Default sorting for DirectoryItem sub-dirrectories.
- * @param {!Array<!Entry>} entries Entries to be sorted.
- * @returns {!Array<!Entry>}
- */
-DirectoryItem.prototype.sortEntries = function(entries) {
-  entries.sort(util.compareName);
-  const filter = this.fileFilter_.filter.bind(this.fileFilter_);
-  return entries.filter(filter);
-};
-
 /**
  * Retrieves the latest subdirectories and update them on the tree.
  * @param {boolean} recursive True if the update is recursively.
@@ -501,11 +490,17 @@ DirectoryItem.prototype.sortEntries = function(entries) {
  */
 DirectoryItem.prototype.updateSubDirectories = function(
     recursive, opt_successCallback, opt_errorCallback) {
-  if (!this.entry || this.entry.createReader === undefined) {
-    opt_errorCallback && opt_errorCallback();
+  if (!this.entry || util.isFakeEntry(this.entry)) {
+    if (opt_errorCallback)
+      opt_errorCallback();
     return;
   }
 
+  const sortEntries = (fileFilter, entries) => {
+    entries.sort(util.compareName);
+    return entries.filter(fileFilter.filter.bind(fileFilter));
+  };
+
   const onSuccess = (entries) => {
     this.entries_ = entries;
     this.updateSubElementsFromList(recursive);
@@ -517,7 +512,7 @@ DirectoryItem.prototype.updateSubDirectories = function(
   const readEntry = () => {
     reader.readEntries((results) => {
       if (!results.length) {
-        onSuccess(this.sortEntries(entries));
+        onSuccess(sortEntries(this.fileFilter_, entries));
         return;
       }
 
@@ -748,46 +743,26 @@ EntryListItem.prototype = {
  */
 EntryListItem.prototype.updateSubDirectories = function(
     recursive, opt_successCallback, opt_errorCallback) {
-  if (!this.entry || this.entry.createReader === undefined) {
+  if (!this.entry) {
     opt_errorCallback && opt_errorCallback();
     return;
   }
   this.entries_ = [];
-
-  const onSuccess = (entries) => {
-    this.entries_ = entries;
-    this.updateSubElementsFromList(recursive);
-    if (this.entries_.length > 0)
-      this.expanded = true;
-    opt_successCallback && opt_successCallback();
-    // TODO(lucmult): Remove this log once flakiness is fixed.
-    console.log('EntryListItem children loaded.');
-  };
-
-  const reader = this.entry.createReader();
-  const entries = [];
-  const readEntry = () => {
-    reader.readEntries((results) => {
-      if (!results.length) {
-        onSuccess(this.sortEntries(entries));
-        return;
-      }
-
-      for (let i = 0; i < results.length; i++) {
-        const entry = results[i];
-        if (entry.isDirectory) {
-          // For VolumeEntry we want to display its root.
-          if (entry instanceof VolumeEntry) {
-            entries.push(entry.rootEntry);
-          } else {
-            entries.push(entry);
-          }
-        }
+  if (this.entry && this.entry.children) {
+    for (let childEntry of this.entry.children) {
+      if (childEntry instanceof VolumeEntry) {
+        // For VolumeEntry we want to display its root.
+        this.entries_.push(childEntry.rootEntry);
+      } else {
+        this.entries_.push(childEntry);
       }
-      readEntry();
-    });
-  };
-  readEntry();
+    }
+  }
+  if (this.entries_.length > 0) {
+    this.expanded = true;
+  }
+  this.updateSubElementsFromList(recursive);
+  opt_successCallback && opt_successCallback();
 };
 
 ////////////////////////////////////////////////////////////////////////////////

ui/file_manager/file_manager/foreground/js/ui/directory_tree_unittest.js

@@ -501,9 +501,8 @@ function testUpdateSubElementsFromListSections() {
   assertEquals(NavigationSection.MY_FILES, myFilesItem.section);
   assertEquals(NavigationSection.CLOUD, driveItem.section);
 
-  const metadataModel = mockMetadataModel();
   DirectoryTree.decorate(directoryTree, directoryModel, volumeManager,
-      metadataModel, fileOperationManager, true);
+      null, fileOperationManager, true);
   directoryTree.dataModel = treeModel;
   directoryTree.updateSubElementsFromList(false);
 
@@ -959,10 +958,9 @@ function testInsideMyDriveAndInsideDrive(callback) {
       .webkitResolveLocalFileSystemURLEntries['filesystem:downloads/folder1'] =
       new MockDirectoryEntry(downloadsFileSystem, '/folder1');
 
-  const metadataModel = mockMetadataModel();
   DirectoryTree.decorate(
-      directoryTree, directoryModel, volumeManager, metadataModel,
-      fileOperationManager, true);
+      directoryTree, directoryModel, volumeManager, null, fileOperationManager,
+      true);
   directoryTree.dataModel = new MockNavigationListModel(volumeManager);
   directoryTree.redraw(true);