Reland "[Files app] Generate modules for ui/file_manager/.../metadata_proxy.js"

This is a reland of 9d2bdda8

Original change's description:
> [Files app] Generate modules for ui/file_manager/.../metadata_proxy.js
>
> Converted files:
> - ui/file_manager/file_manager/background/js/metadata_proxy.js
> - ui/file_manager/file_manager/background/js/metadata_proxy_unittest.js
>
> Bug: 1133186
> Change-Id: I81eb9d34fff12835ef5974acfee3817fec864340
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2563105
> Commit-Queue: Jeremie Boulic <jboulic@chromium.org>
> Reviewed-by: Luciano Pacheco <lucmult@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#833130}

Bug: 1133186
Change-Id: Idee34300befe5605219967ee7cea0ed803f4aeda
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2573699Reviewed-by: Luciano Pacheco <lucmult@chromium.org>
Auto-Submit: Jeremie Boulic <jboulic@chromium.org>
Commit-Queue: Jeremie Boulic <jboulic@chromium.org>
Cr-Commit-Position: refs/heads/master@{#833622}

chrome/browser/chromeos/file_manager/file_manager_jstest.cc

@@ -201,7 +201,7 @@ IN_PROC_BROWSER_TEST_F(FileManagerJsTest, MetadataModel) {
 }
 
 IN_PROC_BROWSER_TEST_F(FileManagerJsTest, MetadataProxyTest) {
-  RunTestURL("background/js/metadata_proxy_unittest_gen.html");
+  RunTestURL("background/js/metadata_proxy_unittest.m_gen.html");
 }
 
 IN_PROC_BROWSER_TEST_F(FileManagerJsTest, MountMetricsTest) {

ui/file_manager/BUILD.gn

@@ -59,6 +59,7 @@ group("unit_test_data") {
   deps = [
     "base/js:js_test_gen_html",
     "file_manager/background/js:js_test_gen_html",
+    "file_manager/background/js:js_test_gen_html_modules",
     "file_manager/common/js:js_test_gen_html",
     "file_manager/common/js:js_test_gen_html_modules",
     "file_manager/foreground/elements:js_test_gen_html",

ui/file_manager/file_manager/background/js/BUILD.gn

@@ -26,6 +26,7 @@ group("closure_compile") {
   deps = [
     ":closure_compile_jsmodules",
     ":closure_compile_module",
+    ":js_test_gen_html_modules_type_check_auto",
     ":js_test_gen_html_type_check_auto",
     ":test_support_modules_type_check",
     ":test_support_type_check",
@@ -76,6 +77,7 @@ js_type_check("closure_compile_jsmodules") {
     ":app_windows.m",
     ":background_base.m",
     ":entry_location_impl.m",
+    ":metadata_proxy.m",
     ":test_util_base.m",
     ":volume_info_impl.m",
     ":volume_info_list_impl.m",
@@ -392,11 +394,19 @@ js_library("metadata_proxy") {
   deps = [ "//ui/file_manager/file_manager/common/js:lru_cache" ]
 }
 
-js_unittest("metadata_proxy_unittest") {
+js_library("metadata_proxy.m") {
+  sources = [ "$root_gen_dir/ui/file_manager/file_manager/background/js/metadata_proxy.m.js" ]
+  deps = [ "//ui/file_manager/file_manager/common/js:lru_cache.m" ]
+
+  extra_deps = [ ":modulize" ]
+}
+
+js_unittest("metadata_proxy_unittest.m") {
   deps = [
-    ":metadata_proxy",
-    "//ui/file_manager/base/js:test_error_reporting",
-    "//ui/file_manager/file_manager/common/js:mock_entry",
+    ":metadata_proxy.m",
+    "//chrome/test/data/webui:chai_assert",
+    "//ui/file_manager/base/js:test_error_reporting.m",
+    "//ui/file_manager/file_manager/common/js:mock_entry.m",
   ]
 }
 
@@ -773,6 +783,19 @@ js_library("volume_manager_util.m") {
   extra_deps = [ ":modulize" ]
 }
 
+js_test_gen_html("js_test_gen_html_modules") {
+  deps = [ ":metadata_proxy_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/=./\"",
+        "hide_warnings_for=third_party/",
+      ]
+}
+
 js_test_gen_html("js_test_gen_html") {
   deps = [
     ":crostini_unittest",
@@ -784,7 +807,6 @@ js_test_gen_html("js_test_gen_html") {
     ":import_history_unittest",
     ":media_import_handler_unittest",
     ":media_scanner_unittest",
-    ":metadata_proxy_unittest",
     ":mount_metrics_unittest",
     ":task_queue_unittest",
     ":trash_unittest",
@@ -794,6 +816,7 @@ js_test_gen_html("js_test_gen_html") {
 
 js_modulizer("modulize") {
   input_files = [
+    "metadata_proxy.js",
     "app_windows.js",
     "app_window_wrapper.js",
     "background_base.js",

ui/file_manager/file_manager/background/js/metadata_proxy.js

@@ -2,6 +2,13 @@
 // 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.
+ */
+
+// #import {LRUCache} from '../../common/js/lru_cache.m.js';
+
 // Namespace
 const metadataProxy = {};
 
@@ -76,3 +83,6 @@ metadataProxy.getEntryMetadata = entry => {
 metadataProxy.overrideCacheTtlForTesting = ttl => {
   metadataProxy.cache_ttl_seconds_ = ttl ? ttl : metadataProxy.MAX_TTL_SECONDS_;
 };
+
+// eslint-disable-next-line semi,no-extra-semi
+/* #export */ {metadataProxy};

ui/file_manager/file_manager/background/js/metadata_proxy_unittest.js → ui/file_manager/file_manager/background/js/metadata_proxy_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.
 
-function testMetadataCaching(doneCallback) {
+// clang-format off
+import {assertEquals} from 'chrome://test/chai_assert.js';
+import {reportPromise} from '../../../base/js/test_error_reporting.m.js';
+import {MockFileSystem} from '../../common/js/mock_entry.m.js';
+import {metadataProxy} from './metadata_proxy.m.js';
+// clang-format on
+
+export function testMetadataCaching(doneCallback) {
   reportPromise(
       (async function() {
         const mockFileSystem = new MockFileSystem('volumeId');
@@ -30,7 +37,7 @@ function testMetadataCaching(doneCallback) {
       doneCallback);
 }
 
-function testMetadataCacheExpiry(doneCallback) {
+export function testMetadataCacheExpiry(doneCallback) {
   reportPromise(
       (async function() {
         const mockFileSystem = new MockFileSystem('volumeId');