Audio player: Convert //ui/.../metadata/exif_parser and dependencies

JS Modules for the following files:

//ui/file_manager/file_manager/foreground/js/metadata/:
- exif_parser.js
- exif_parser_unittest.js

//ui/file_manager/externs/:
- exif_entry.js

//ui/file_manager/gallery/js/image_editor/:
- test_util.js
- image_util.js
- image_encoder.js
- image_encoder_unittest.js
- exif_encoder.js
- exif_encoder_unittest.js
- exif_parser.js
- exif_parser_unittest.js

Bug: 1133186
Change-Id: I696fde015e7f8bbea44544ef8721aed2e9a1a59d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2536660
Commit-Queue: Jeremie Boulic <jboulic@chromium.org>
Auto-Submit: Jeremie Boulic <jboulic@chromium.org>
Reviewed-by: Luciano Pacheco <lucmult@chromium.org>
Cr-Commit-Position: refs/heads/master@{#827723}

chrome/browser/chromeos/file_manager/file_manager_jstest.cc

@@ -62,7 +62,7 @@ IN_PROC_BROWSER_TEST_F(FileManagerJsTest, DuplicateFinderTest) {
 }
 
 IN_PROC_BROWSER_TEST_F(FileManagerJsTest, ExifParser) {
-  RunTestURL("foreground/js/metadata/exif_parser_unittest_gen.html");
+  RunTestURL("foreground/js/metadata/exif_parser_unittest.m_gen.html");
 }
 
 IN_PROC_BROWSER_TEST_F(FileManagerJsTest, ExternalMetadataProvider) {

chrome/browser/chromeos/file_manager/gallery_jstest.cc

@@ -13,7 +13,7 @@ class GalleryJsTest : public FileManagerJsTestBase {
 };
 
 IN_PROC_BROWSER_TEST_F(GalleryJsTest, ImageEncoderTest) {
-  RunTestURL("image_editor/image_encoder_unittest_gen.html");
+  RunTestURL("image_editor/image_encoder_unittest.m_gen.html");
 }
 
 // Disabled on ASan builds due to a consistent failure. https://crbug.com/762831
@@ -23,7 +23,7 @@ IN_PROC_BROWSER_TEST_F(GalleryJsTest, ImageEncoderTest) {
 #define MAYBE_ExifEncoderTest ExifEncoderTest
 #endif
 IN_PROC_BROWSER_TEST_F(GalleryJsTest, MAYBE_ExifEncoderTest) {
-  RunTestURL("image_editor/exif_encoder_unittest_gen.html");
+  RunTestURL("image_editor/exif_encoder_unittest.m_gen.html");
 }
 
 IN_PROC_BROWSER_TEST_F(GalleryJsTest, ImageViewTest) {

ui/file_manager/BUILD.gn

@@ -68,6 +68,7 @@ group("unit_test_data") {
     "file_manager/foreground/js/ui:js_test_gen_html",
     "gallery/js:js_test_gen_html",
     "gallery/js/image_editor:js_test_gen_html",
+    "gallery/js/image_editor:js_test_gen_html_modules",
     "image_loader:js_test_gen_html",
     "image_loader:js_test_gen_html_modules",
     "video_player/js:js_test_gen_html",

ui/file_manager/externs/BUILD.gn

@@ -37,6 +37,16 @@ js_library("entry_location.m") {
   extra_deps = [ ":modulize" ]
 }
 
+js_library("exif_entry.m") {
+  sources = [ "$root_gen_dir/ui/file_manager/externs/exif_entry.m.js" ]
+
+  deps = [
+    "//ui/file_manager/file_manager/foreground/js/metadata:exif_constants.m",
+  ]
+
+  extra_deps = [ ":modulize" ]
+}
+
 js_library("files_app_entry_interfaces.m") {
   sources = [
     "$root_gen_dir/ui/file_manager/externs/files_app_entry_interfaces.m.js",
@@ -105,6 +115,7 @@ js_modulizer("modulize") {
   input_files = [
     "background_window.js",
     "entry_location.js",
+    "exif_entry.js",
     "files_app_entry_interfaces.js",
     "metadata_worker_window.js",
     "volume_info.js",

ui/file_manager/externs/exif_entry.js

@@ -2,9 +2,13 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+// clang-format off
+// #import * as wrappedExif from '../file_manager/foreground/js/metadata/exif_constants.m.js'; const {Exif} = wrappedExif;
+// clang-format on
+
 /**
  * Type definition of exif entry.
  * @typedef {{id:!Exif.Tag, format:number, componentCount:number,
  *     value:(undefined|*)}}
  */
-var ExifEntry;
+/* #export */ let ExifEntry;

ui/file_manager/file_manager/foreground/js/metadata/BUILD.gn

@@ -25,6 +25,7 @@ js_type_check("closure_compile_jsmodules") {
   deps = [
     ":byte_reader.m",
     ":exif_constants.m",
+    ":exif_parser.m",
     ":external_metadata_provider.m",
     ":file_system_metadata_provider.m",
     ":function_parallel.m",
@@ -109,11 +110,28 @@ js_library("exif_parser") {
   externs_list = [ "//ui/file_manager/externs/exif_entry.js" ]
 }
 
-js_unittest("exif_parser_unittest") {
+js_library("exif_parser.m") {
+  sources = [ "$root_gen_dir/ui/file_manager/file_manager/foreground/js/metadata/exif_parser.m.js" ]
   deps = [
-    ":exif_parser",
-    "//ui/file_manager/base/js:test_error_reporting",
-    "//ui/file_manager/gallery/js/image_editor:exif_encoder",
+    ":byte_reader.m",
+    ":exif_constants.m",
+    ":metadata_parser.m",
+    "//ui/file_manager/externs:exif_entry.m",
+    "//ui/file_manager/externs:metadata_worker_window.m",
+  ]
+
+  extra_deps = [ ":modulize" ]
+}
+
+js_unittest("exif_parser_unittest.m") {
+  deps = [
+    ":byte_reader.m",
+    ":exif_constants.m",
+    ":exif_parser.m",
+    "//chrome/test/data/webui:chai_assert",
+    "//ui/file_manager/externs:exif_entry.m",
+    "//ui/file_manager/externs:metadata_worker_window.m",
+    "//ui/file_manager/gallery/js/image_editor:exif_encoder.m",
   ]
 }
 
@@ -410,6 +428,7 @@ js_unittest("thumbnail_model_unittest") {
 
 js_test_gen_html("js_test_gen_html_modules") {
   deps = [
+    ":exif_parser_unittest.m",
     ":external_metadata_provider_unittest.m",
     ":file_system_metadata_provider_unittest.m",
     ":image_orientation_unittest.m",
@@ -417,17 +436,17 @@ js_test_gen_html("js_test_gen_html_modules") {
   ]
   js_module = true
 
-  closure_flags = strict_error_checking_closure_args + [
-                    "js_module_root=./gen/ui/file_manager/file_manager/foreground/js/metadata",
-                    "js_module_root=../../ui/file_manager/file_manager/foreground/js/metadata",
-                    "browser_resolver_prefix_replacements=\"chrome://test/=./\"",
-                  ]
+  closure_flags =
+      strict_error_checking_closure_args + [
+        "js_module_root=./gen/ui",
+        "js_module_root=../../ui",
+        "browser_resolver_prefix_replacements=\"chrome://test/=./\"",
+      ]
 }
 
 js_test_gen_html("js_test_gen_html") {
   deps = [
     ":content_metadata_provider_unittest",
-    ":exif_parser_unittest",
     ":metadata_cache_set_unittest",
     ":metadata_model_unittest",
     ":multi_metadata_provider_unittest",
@@ -440,6 +459,7 @@ js_modulizer("modulize") {
   input_files = [
     "byte_reader.js",
     "exif_constants.js",
+    "exif_parser.js",
     "external_metadata_provider.js",
     "file_system_metadata_provider.js",
     "function_parallel.js",

ui/file_manager/file_manager/foreground/js/metadata/exif_parser.js

@@ -2,11 +2,19 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-importScripts(
-    'chrome-extension://hhaomjibdihmijegdhdafkllkbggdgoj/foreground/js/metadata/exif_constants.js');
+// clang-format off
+// #import {ByteReader} from './byte_reader.m.js';
+// #import * as wrappedExif from './exif_constants.m.js'; const {Exif} = wrappedExif;
+// #import {ImageParser} from './metadata_parser.m.js';
+// #import {ExifEntry} from '../../../../externs/exif_entry.m.js';
+// #import {MetadataParserLogger} from '../../../../externs/metadata_worker_window.m.js';
+
+/* #ignore */ importScripts(
+/* #ignore */     'chrome-extension://hhaomjibdihmijegdhdafkllkbggdgoj/foreground/js/metadata/exif_constants.js');
+// clang-format on
 
 /** @final */
-class ExifParser extends ImageParser {
+/* #export */ class ExifParser extends ImageParser {
   /**
    * @param {!MetadataParserLogger} parent Parent object.
    */
@@ -274,7 +282,7 @@ class ExifParser extends ImageParser {
   readDirectory(br, tags) {
     const entryCount = br.readScalar(2);
     for (let i = 0; i < entryCount; i++) {
-      const tagId = /** @type Exif.Tag<number> */ (br.readScalar(2));
+      const tagId = /** @type !Exif.Tag<number> */ (br.readScalar(2));
       const tag = tags[tagId] = {id: tagId};
       tag.format = br.readScalar(2);
       tag.componentCount = br.readScalar(4);

ui/file_manager/file_manager/foreground/js/metadata/exif_parser_unittest.js → ui/file_manager/file_manager/foreground/js/metadata/exif_parser_unittest.m.js

@@ -2,6 +2,15 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import {assertEquals, assertTrue} from 'chrome://test/chai_assert.js';
+import {ByteWriter} from '../../../../gallery/js/image_editor/exif_encoder.m.js';
+import {ByteReader} from './byte_reader.m.js';
+import * as wrappedExif from './exif_constants.m.js';
+import {ExifParser} from './exif_parser.m.js';
+const {Exif} = wrappedExif;
+import {ExifEntry} from '../../../../externs/exif_entry.m.js';
+import {MetadataParserLogger} from '../../../../externs/metadata_worker_window.m.js';
+
 /**
  * Creates a directory with specified tag. This method only supports string
  * format tag, which is longer than 4 characters.
@@ -68,7 +77,7 @@ function parseExifData_(bytes) {
 /**
  * Tests that parsed exif strings have a null character termination.
  */
-function testWithoutNullCharacterTermination() {
+export function testWithoutNullCharacterTermination() {
   // Create exif with a value that does not end with null character.
   const data = new Uint8Array(0x10000);
   writeDirectory_(data, /** @type {!ExifEntry} */ ({

ui/file_manager/gallery/js/image_editor/BUILD.gn

@@ -5,6 +5,17 @@
 import("//third_party/closure_compiler/compile_js.gni")
 import("//third_party/closure_compiler/js_unit_tests.gni")
 import("//ui/file_manager/base/gn/js_test_gen_html.gni")
+import("//ui/webui/resources/tools/js_modulizer.gni")
+
+js_type_check("closure_compile_jsmodules") {
+  uses_js_modules = true
+  deps = [
+    ":exif_encoder.m",
+    ":image_encoder.m",
+    ":image_util.m",
+    ":test_util.m",
+  ]
+}
 
 js_type_check("closure_compile_module") {
   deps = [
@@ -48,12 +59,31 @@ js_library("exif_encoder") {
   externs_list = [ "//ui/file_manager/externs/exif_entry.js" ]
 }
 
-js_unittest("exif_encoder_unittest") {
+js_library("exif_encoder.m") {
+  sources = [
+    "$root_gen_dir/ui/file_manager/gallery/js/image_editor/exif_encoder.m.js",
+  ]
   deps = [
-    ":exif_encoder",
-    ":test_util",
-    "//ui/file_manager/file_manager/foreground/js/metadata:exif_parser",
-    "//ui/webui/resources/js:webui_resource_test",
+    ":image_encoder.m",
+    "//ui/file_manager/externs:exif_entry.m",
+    "//ui/file_manager/file_manager/foreground/js/metadata:exif_constants.m",
+    "//ui/file_manager/file_manager/foreground/js/metadata:metadata_item.m",
+    "//ui/webui/resources/js:assert.m",
+  ]
+
+  extra_deps = [ ":modulize" ]
+}
+
+js_unittest("exif_encoder_unittest.m") {
+  deps = [
+    ":exif_encoder.m",
+    ":image_encoder.m",
+    ":test_util.m",
+    "//chrome/test/data/webui:chai_assert",
+    "//ui/file_manager/externs:metadata_worker_window.m",
+    "//ui/file_manager/file_manager/foreground/js/metadata:byte_reader.m",
+    "//ui/file_manager/file_manager/foreground/js/metadata:exif_parser.m",
+    "//ui/file_manager/file_manager/foreground/js/metadata:metadata_item.m",
   ]
 }
 
@@ -117,12 +147,26 @@ js_library("image_encoder") {
   ]
 }
 
-js_unittest("image_encoder_unittest") {
+js_library("image_encoder.m") {
+  sources = [
+    "$root_gen_dir/ui/file_manager/gallery/js/image_editor/image_encoder.m.js",
+  ]
   deps = [
-    ":image_encoder",
-    ":test_util",
-    "//ui/file_manager/base/js:test_error_reporting",
-    "//ui/file_manager/file_manager/foreground/js/metadata:metadata_parser",
+    ":image_util.m",
+    "//ui/file_manager/file_manager/foreground/js/metadata:metadata_item.m",
+    "//ui/webui/resources/js:assert.m",
+  ]
+
+  extra_deps = [ ":modulize" ]
+}
+
+js_unittest("image_encoder_unittest.m") {
+  deps = [
+    ":image_encoder.m",
+    ":test_util.m",
+    "//chrome/test/data/webui:chai_assert",
+    "//ui/file_manager/base/js:test_error_reporting.m",
+    "//ui/file_manager/file_manager/foreground/js/metadata:metadata_item.m",
   ]
   externs_list = [ "//ui/file_manager/externs/metadata_worker_window.js" ]
 }
@@ -161,6 +205,15 @@ js_library("image_util") {
   deps = [ "//ui/webui/resources/js:assert" ]
 }
 
+js_library("image_util.m") {
+  sources = [
+    "$root_gen_dir/ui/file_manager/gallery/js/image_editor/image_util.m.js",
+  ]
+  deps = [ "//ui/webui/resources/js:assert.m" ]
+
+  extra_deps = [ ":modulize" ]
+}
+
 js_library("image_view") {
   deps = [
     ":image_buffer",
@@ -185,6 +238,14 @@ js_unittest("image_view_unittest") {
 js_library("test_util") {
 }
 
+js_library("test_util.m") {
+  sources =
+      [ "$root_gen_dir/ui/file_manager/gallery/js/image_editor/test_util.m.js" ]
+  deps = [ "//ui/webui/resources/js:assert.m" ]
+
+  extra_deps = [ ":modulize" ]
+}
+
 js_library("viewport") {
   deps = [
     ":image_util",
@@ -192,19 +253,41 @@ js_library("viewport") {
   ]
 }
 
-js_test_gen_html("js_test_gen_html") {
+js_test_gen_html("js_test_gen_html_modules") {
   deps = [
-    ":exif_encoder_unittest",
-    ":image_encoder_unittest",
-    ":image_view_unittest",
+    ":exif_encoder_unittest.m",
+    ":image_encoder_unittest.m",
   ]
+  js_module = true
+
+  closure_flags =
+      strict_error_checking_closure_args + [
+        "js_module_root=./gen/ui",
+        "js_module_root=../../ui",
+        "browser_resolver_prefix_replacements=\"chrome://test/=./\"",
+      ]
+}
+
+js_test_gen_html("js_test_gen_html") {
+  deps = [ ":image_view_unittest" ]
   mocks = [ "//ui/file_manager/file_manager/foreground/js/metadata/metadata_dispatcher_mock_deps.js" ]
 }
 
 group("closure_compile") {
   testonly = true
   deps = [
+    ":closure_compile_jsmodules",
     ":closure_compile_module",
+    ":js_test_gen_html_modules_type_check_auto",
     ":js_test_gen_html_type_check_auto",
   ]
 }
+
+js_modulizer("modulize") {
+  input_files = [
+    "exif_encoder.js",
+    "image_encoder.js",
+    "image_util.js",
+    "test_util.js",
+  ]
+}

ui/file_manager/gallery/js/image_editor/exif_encoder.js

@@ -2,6 +2,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+/* eslint-disable no-var */
+
+// clang-format off
+// #import {ImageEncoder} from './image_encoder.m.js';
+// #import * as wrappedExif from '../../../file_manager/foreground/js/metadata/exif_constants.m.js'; const {Exif} = wrappedExif;
+// #import {MetadataItem} from '../../../file_manager/foreground/js/metadata/metadata_item.m.js';
+// #import {assert} from 'chrome://resources/js/assert.m.js'
+// #import {ExifEntry} from '../../../externs/exif_entry.m.js';
+// clang-format on
+
 /**
  * The Exif metadata encoder.
  * Uses the metadata format as defined by ExifParser.
@@ -10,7 +20,7 @@
  * @extends {ImageEncoder.MetadataEncoder}
  * @struct
  */
-function ExifEncoder(originalMetadata) {
+/* #export */ function ExifEncoder(originalMetadata) {
   ImageEncoder.MetadataEncoder.apply(this, arguments);
   /**
    * Image File Directory obtained from EXIF header.
@@ -473,7 +483,7 @@ ExifEncoder.findOrCreateTag = function(directory, id, opt_format,
  * @constructor
  * @struct
  */
-function ByteWriter(arrayBuffer, offset, opt_length) {
+/* #export */ function ByteWriter(arrayBuffer, offset, opt_length) {
   var length = opt_length || (arrayBuffer.byteLength - offset);
   this.view_ = new DataView(arrayBuffer, offset, length);
   this.littleEndian_ = false;

ui/file_manager/gallery/js/image_editor/exif_encoder_unittest.js → ui/file_manager/gallery/js/image_editor/exif_encoder_unittest.m.js

@@ -2,7 +2,14 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-'use strict';
+import {assertEquals, assertTrue} from 'chrome://test/chai_assert.js';
+import {MetadataParserLogger} from '../../../externs/metadata_worker_window.m.js';
+import {ByteReader} from '../../../file_manager/foreground/js/metadata/byte_reader.m.js';
+import {ExifParser} from '../../../file_manager/foreground/js/metadata/exif_parser.m.js';
+import {MetadataItem} from '../../../file_manager/foreground/js/metadata/metadata_item.m.js';
+import {ExifEncoder} from './exif_encoder.m.js';
+import {ImageEncoder} from './image_encoder.m.js';
+import {getSampleCanvas} from './test_util.m.js';
 
 /**
  * @implements {MetadataParserLogger}
@@ -21,7 +28,7 @@ class NoLogger {
 /**
  * Test case for ordinal exif encoding and decoding.
  */
-function testExifEncodeAndDecode() {
+export function testExifEncodeAndDecode() {
   const canvas = getSampleCanvas();
   const data = canvas.toDataURL('image/jpeg');
 
@@ -166,7 +173,7 @@ function largeExifDataTestHelper_(largeFieldValueSize, expectThumbnail) {
 /**
  * Test case when other exif data is small as the thumbnail can fit in.
  */
-function testLargeExifDataSmallCase() {
+export function testLargeExifDataSmallCase() {
   // 158 bytes: other exif data except value of the large field.
   largeExifDataTestHelper_(
       ExifEncoder.MAXIMUM_EXIF_DATA_SIZE - measureExpectedThumbnailSize_() -
@@ -177,7 +184,7 @@ function testLargeExifDataSmallCase() {
 /**
  * Test case when other exif data is large as the thumbnail can just fit in.
  */
-function testLargeExifDataBoundaryCase() {
+export function testLargeExifDataBoundaryCase() {
   largeExifDataTestHelper_(
       ExifEncoder.MAXIMUM_EXIF_DATA_SIZE - measureExpectedThumbnailSize_() -
           ExifEncoder.THUMBNAIL_METADATA_SIZE - 158,
@@ -187,7 +194,7 @@ function testLargeExifDataBoundaryCase() {
 /**
  * Test case when other exif data is large as the thumbnail cannot fit in.
  */
-function testLargeExifDataExceedsCase() {
+export function testLargeExifDataExceedsCase() {
   largeExifDataTestHelper_(
       ExifEncoder.MAXIMUM_EXIF_DATA_SIZE - measureExpectedThumbnailSize_() -
           ExifEncoder.THUMBNAIL_METADATA_SIZE - 158 + 1,

ui/file_manager/gallery/js/image_editor/image_encoder.js

@@ -2,11 +2,19 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+/* eslint-disable no-var */
+
+// clang-format off
+// #import * as wrappedImageUtil from './image_util.m.js'; const {ImageUtil} = wrappedImageUtil;
+// #import {MetadataItem} from '../../../file_manager/foreground/js/metadata/metadata_item.m.js';
+// #import {assert, assertInstanceof} from 'chrome://resources/js/assert.m.js'
+// clang-format on
+
 /**
  * A namespace class for image encoding functions. All methods are static.
  * @constructor
  */
-function ImageEncoder() {}
+/* #export */ function ImageEncoder() {}
 
 /**
  * The value 360 px is enough in the Files app grid view for HiDPI devices.

ui/file_manager/gallery/js/image_editor/image_encoder_unittest.js → ui/file_manager/gallery/js/image_editor/image_encoder_unittest.m.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.
-'use strict';
+
+/* eslint-disable no-var */
+
+import {assertEquals, assertThrows} from 'chrome://test/chai_assert.js';
+import {reportPromise} from '../../../base/js/test_error_reporting.m.js';
+import {MetadataItem} from '../../../file_manager/foreground/js/metadata/metadata_item.m.js';
+import {ImageEncoder} from './image_encoder.m.js';
+import {getSampleCanvas} from './test_util.m.js';
 
 /**
  * Encodes an image to data URL by using ImageEncoder.getBlob.
@@ -27,17 +34,16 @@ function encodeAnImageAsDataURL(canvas, metadata, imageQuality) {
  * Test case for png image.
  * Png image should be saved as a png image.
  */
-function testPngImage(callback) {
+export function testPngImage(callback) {
   var canvas = getSampleCanvas();
 
-  var metadata = {
-    mediaMimeType: 'image/png'
-  };
+  var metadata = {mediaMimeType: 'image/png'};
 
-  reportPromise(encodeAnImageAsDataURL(canvas, metadata, 0.9).then(
-      function(result) {
+  reportPromise(
+      encodeAnImageAsDataURL(canvas, metadata, 0.9).then(function(result) {
         assertEquals(canvas.toDataURL('image/png'), result);
-      }), callback);
+      }),
+      callback);
 }
 
 /**
@@ -45,17 +51,16 @@ function testPngImage(callback) {
  * Jpeg image should be saved as a jpeg image. Since we don't include
  * exif_encoder.js in this test, no metadata is added to the blob.
  */
-function testJpegImage(callback) {
+export function testJpegImage(callback) {
   var canvas = getSampleCanvas();
 
-  var metadata = {
-    mediaMimeType: 'image/jpeg'
-  };
+  var metadata = {mediaMimeType: 'image/jpeg'};
 
-  reportPromise(encodeAnImageAsDataURL(canvas, metadata, 0.9).then(
-      function(result) {
+  reportPromise(
+      encodeAnImageAsDataURL(canvas, metadata, 0.9).then(function(result) {
         assertEquals(canvas.toDataURL('image/jpeg', 0.9), result);
-      }), callback);
+      }),
+      callback);
 }
 
 
@@ -64,23 +69,22 @@ function testJpegImage(callback) {
  * Image should be saved as a image/png since chrome doesn't support to
  * encode other than image/jpeg or image/png.
  */
-function testWebpImage(callback) {
+export function testWebpImage(callback) {
   var canvas = getSampleCanvas();
 
-  var metadata = {
-    mediaMimeType: 'image/webp'
-  };
+  var metadata = {mediaMimeType: 'image/webp'};
 
-  reportPromise(encodeAnImageAsDataURL(canvas, metadata, 0.9).then(
-      function(result) {
+  reportPromise(
+      encodeAnImageAsDataURL(canvas, metadata, 0.9).then(function(result) {
         assertEquals(canvas.toDataURL('image/png'), result);
-      }), callback);
+      }),
+      callback);
 }
 
 /**
  * Test case for broken metadata.
  */
-function testWithBrokenMetadata() {
+export function testWithBrokenMetadata() {
   var canvas = getSampleCanvas();
 
   var metadata = /** @type {!MetadataItem} */ ({

ui/file_manager/gallery/js/image_editor/image_util.js

@@ -2,6 +2,17 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+/**
+ * @fileoverview
+ * @suppress {uselessCode} Temporary suppress because of the line exporting.
+ */
+
+/* eslint-disable no-var */
+
+// clang-format off
+// #import {assert, assertInstanceof} from 'chrome://resources/js/assert.m.js';
+// clang-format on
+
 // Namespace object for the utilities.
 var ImageUtil = {};
 
@@ -88,7 +99,7 @@ ImageUtil.between = function(min, value, max) {
  * @constructor
  * @struct
  */
-function ImageRect(left, top, width, height) {
+/* #export */ function ImageRect(left, top, width, height) {
   this.left = left;
   this.top = top;
   this.width = width;
@@ -490,3 +501,6 @@ ImageUtil.ensureCanvas = function(imgOrCanvas) {
  * @const
  */
 ImageUtil.FILE_TYPES = ['jpg', 'png', 'gif', 'bmp', 'webp'];
+
+// eslint-disable-next-line semi,no-extra-semi
+/* #export */ {ImageUtil};

ui/file_manager/gallery/js/image_editor/test_util.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.
-'use strict';
+
+/* eslint-disable no-var */
+
+// #import {assert, assertInstanceof} from 'chrome://resources/js/assert.m.js'
+
+/* #ignore */ 'use strict';
 
 /**
  * Creates a sample canvas.
  * @return {!HTMLCanvasElement}
  */
-function getSampleCanvas() {
+/* #export */ function getSampleCanvas() {
   var canvas =
       assertInstanceof(document.createElement('canvas'), HTMLCanvasElement);
   canvas.width = 1920;