Add ImportHistory class and RecordStorage class.

chrome/test/data/file_manager/unit_tests/import_history_unittest.js

Index: chrome/test/data/file_manager/unit_tests/import_history_unittest.js
diff --git a/chrome/test/data/file_manager/unit_tests/import_history_unittest.js b/chrome/test/data/file_manager/unit_tests/import_history_unittest.js
new file mode 100644
index 0000000000000000000000000000000000000000..fed2e53391b2c5c1a6b5e9d3226c216a05aa9812
--- /dev/null
+++ b/chrome/test/data/file_manager/unit_tests/import_history_unittest.js
@@ -0,0 +1,174 @@
+// 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.
+'use strict';
+
+/** @const {string} */
+var FILE_LAST_MODIFIED = new Date("Dec 4 1968").toString();
+
+/** @const {string} */
+var FILE_SIZE = 1234;
+
+/** @const {string} */
+var FILE_PATH = 'test/data';
+
+/** @const {string} */
+var GOOGLE_DRIVE = 'Google Drive';
+
+/**
+ * Space Cloud: Your source for interstellar cloud storage.
+ * @const {string}
+ */
+var SPACE_CLOUD = 'Space Cloud';
+
+/** @type {!TestFileSystem|undefined} */
+var testFileSystem;
+
+/** @type {!MockFileEntry|undefined} */
+var testFileEntry;
+
+/** @type {!RecordStorage|undefined} */
+var storage;
+
+/** @type {!Promise.<ImportHistory>|undefined} */
+var historyLoader;
+
+// Set up the test components.
+function setUp() {
+  testFileSystem = new TestFileSystem('abc-123');
+  testFileEntry = new MockFileEntry(
+      testFileSystem,
+      FILE_PATH, {
+        size: FILE_SIZE,
+        modificationTime: FILE_LAST_MODIFIED
+      });
+
+  storage = new TestRecordStorage();
+  historyLoader = ImportHistory.load(storage);
+}
+
+/**
+ * In-memory test implementation of {@code RecordStorage}.
+ *
+ * @constructor
+ * @implements {RecordStorage}
+ */
+var TestRecordStorage = function() {
+
+  // Pre-populate the store with some "previously written" data <wink>.
+  /** @private {!Array.<!Array.<string>>} */
+  this.records_ = [
+    [FILE_LAST_MODIFIED + '_' + FILE_SIZE, GOOGLE_DRIVE],
+    ['99999_99999', SPACE_CLOUD]
+  ];
+
+  /**
+   * @override
+   * @this {TestRecordStorage}
+   */
+  this.readAll = function() {
+    return Promise.resolve(this.records_);
+  };
+
+  /**
+   * @override
+   * @this {TestRecordStorage}
+   */
+  this.write = function(record) {
+    this.records_.push(record);
+    return Promise.resolve();
+  };
+};
+
+/**
+ * @return {!Promise.<RecordStorage>}
+ */
+function createRealStorage() {
+  return new Promise(
+      function(resolve, reject) {
+        var onFilesystemReady = function(fileSystem) {
+          fileSystem.root.getFile(
+              'test.data',
+              {
+                create: true,
+                exclusive: false
+              },
+              function(fileEntry) {
+                resolve(new FileEntryRecordStorage(fileEntry));
+              },
+              reject);
+        };
+
+        window.webkitRequestFileSystem(
+            TEMPORARY,
+            1024 * 1024,
+            onFilesystemReady,
+            reject);
+      });
+}
+
+function testRecordStorageRemembersPreviouslyWrittenRecords(callback) {
+  createRealStorage()
+      .then(
+          function(storage) {
+            storage.write(['abc', '123']).then(
+                function() {
+                  storage.readAll().then(
+                      function(records) {
+                        callback(/* error */ records.length != 1);
+                      },
+                      callback);
+                });
+            },
+            callback)
+      .catch(handleError.bind(callback));
+}
+
+function testHistoryWasImportedFalseForUnknownEntry(callback) {
+  // TestRecordWriter is pre-configured with a Space Cloud entry
+  // but not for this file.
+  historyLoader.then(
+      function(testHistory) {
+        testHistory.wasImported(testFileEntry, SPACE_CLOUD).then(
+          function(result) {
+            callback(/* error */ result);
+          });
+      })
+  .catch(handleError.bind(callback));
+}
+
+function testHistoryWasImportedTrueForKnownEntryLoadedFromStorage(callback) {
+  // TestRecordWriter is pre-configured with this entry.
+  historyLoader.then(
+      function(testHistory) {
+        testHistory.wasImported(testFileEntry, GOOGLE_DRIVE).then(
+          function(result) {
+            callback(/* error */ !result);
+          });
+      })
+  .catch(handleError.bind(callback));
+}
+
+function testHistoryWasImportedTrueForKnownEntrySetAtRuntime(callback) {
+  historyLoader.then(
+      function(testHistory) {
+        testHistory.markImported(testFileEntry, SPACE_CLOUD).then(
+            function() {
+              testHistory.wasImported(testFileEntry, SPACE_CLOUD).then(
+                  function(result) {
+                    callback(/* error */ !result);
+                  });
+            });
+      })
+  .catch(handleError.bind(callback));
+}
+
+/**
+ * Shared error handler.
+ * @param {function()} callback
+ * @param {!Object} error
+ */
+function handleError(callback, error) {
+  console.error(error.stack || error);
+  callback(/* error */ true);
+}