[CCA] Convert filesystem.js into ES6 module.

Bug: 141518780
Test: Pass closure compiler check, tast run <DUT> 'camera.CCAUI*' and manually
validate tooltips function of CCA works correctly.

Change-Id: I64a2daeae981c6de8d200ac618a63bb55840f992
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1982503
Commit-Queue: Kuo Jen Wei <inker@chromium.org>
Auto-Submit: Kuo Jen Wei <inker@chromium.org>
Reviewed-by: Shik Chen <shik@chromium.org>
Cr-Commit-Position: refs/heads/master@{#727551}

chrome/browser/resources/chromeos/camera/src/js/main.js

@@ -161,8 +161,9 @@ cca.App = class {
               });
         })
         .then((external) => {
-          cca.assert(cca.models.FileSystem.externalDir !== null);
-          this.galleryButton_.initialize(cca.models.FileSystem.externalDir);
+          const externalDir = cca.models.FileSystem.getExternalDirectory();
+          cca.assert(externalDir !== null);
+          this.galleryButton_.initialize(externalDir);
           cca.nav.open(cca.views.ViewName.CAMERA);
         })
         .catch((error) => {

chrome/browser/resources/chromeos/camera/src/js/models/BUILD.gn

@@ -21,7 +21,7 @@ js_library("filenamer") {
 
 js_library("filesystem") {
   deps = [
-    "..:util",
+    "../browser_proxy:browser_proxy",
   ]
 }
 

chrome/browser/resources/chromeos/camera/src/js/namespace.js

@@ -11,7 +11,9 @@
 var cca = {
   device: {},
   intent: {},
-  models: {},
+  models: {
+    FileSystem: {},
+  },
   mojo: {},
   nav: {},
   perf: {},

chrome/browser/resources/chromeos/camera/src/views/main.html

@@ -28,7 +28,7 @@
     <script type="module" src="../js/device/device_info_updater.js"></script>
     <script type="module" src="../js/models/filenamer.js"></script>
     <script defer src="../js/gallerybutton.js"></script>
-    <script defer src="../js/models/filesystem.js"></script>
+    <script type="module" src="../js/models/filesystem.js"></script>
     <script defer src="../js/models/result_saver.js"></script>
     <script defer src="../js/models/video_saver_interface.js"></script>
     <script defer src="../js/models/file_video_saver.js"></script>