Refactor Crostini USB page to replace getter with ready event

Replace getCrostiniSharedUsbDevices with event sent when page is ready.
This matches the Plugin VM USB page.

Bug: 1129266
Change-Id: I97ee3e60129a59c3f616552d6ffa27f7be443767
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2415708Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Reviewed-by: Regan Hsu <hsuregan@chromium.org>
Commit-Queue: Joel Hockey <joelhockey@chromium.org>
Cr-Commit-Position: refs/heads/master@{#808175}

chrome/browser/resources/settings/chromeos/crostini_page/crostini_browser_proxy.js

@@ -74,10 +74,8 @@ cr.define('settings', function() {
      */
     getCrostiniSharedPathsDisplayText(paths) {}
 
-    /**
-     * @return {!Promise<!Array<CrostiniSharedUsbDevice>>}
-     */
-    getCrostiniSharedUsbDevices() {}
+    /** Called when page is ready. */
+    notifyCrostiniSharedUsbDevicesPageReady() {}
 
     /**
      * @param {string} guid Unique device identifier.
@@ -268,8 +266,8 @@ cr.define('settings', function() {
     }
 
     /** @override */
-    getCrostiniSharedUsbDevices() {
-      return cr.sendWithPromise('getCrostiniSharedUsbDevices');
+    notifyCrostiniSharedUsbDevicesPageReady() {
+      return cr.sendWithPromise('notifyCrostiniSharedUsbDevicesPageReady');
     }
 
     /** @override */

chrome/browser/resources/settings/chromeos/crostini_page/crostini_shared_usb_devices.js

@@ -21,14 +21,16 @@ Polymer({
     sharedUsbDevices_: Array,
   },
 
+  /** @private {settings.CrostiniBrowserProxy} */
+  browserProxy_: null,
+
   /** @override */
-  attached() {
+  ready() {
+    this.browserProxy_ = settings.CrostiniBrowserProxyImpl.getInstance();
     this.addWebUIListener(
         'crostini-shared-usb-devices-changed',
         this.onCrostiniSharedUsbDevicesChanged_.bind(this));
-    settings.CrostiniBrowserProxyImpl.getInstance()
-        .getCrostiniSharedUsbDevices()
-        .then(this.onCrostiniSharedUsbDevicesChanged_.bind(this));
+    this.browserProxy_.notifyCrostiniSharedUsbDevicesPageReady();
   },
 
   /**
@@ -45,7 +47,7 @@ Polymer({
    */
   onDeviceSharedChange_(event) {
     const deviceInfo = event.model.item;
-    settings.CrostiniBrowserProxyImpl.getInstance().setCrostiniUsbDeviceShared(
+    this.browserProxy_.setCrostiniUsbDeviceShared(
         deviceInfo.guid, event.target.checked);
     settings.recordSettingChange();
   },

chrome/browser/ui/webui/settings/chromeos/crostini_handler.cc

@@ -74,8 +74,9 @@ void CrostiniHandler::RegisterMessages() {
       base::BindRepeating(&CrostiniHandler::HandleRemoveCrostiniSharedPath,
                           weak_ptr_factory_.GetWeakPtr()));
   web_ui()->RegisterMessageCallback(
-      "getCrostiniSharedUsbDevices",
-      base::BindRepeating(&CrostiniHandler::HandleGetCrostiniSharedUsbDevices,
+      "notifyCrostiniSharedUsbDevicesPageReady",
+      base::BindRepeating(
+          &CrostiniHandler::HandleNotifyCrostiniSharedUsbDevicesPageReady,
           weak_ptr_factory_.GetWeakPtr()));
   web_ui()->RegisterMessageCallback(
       "setCrostiniUsbDeviceShared",
@@ -325,22 +326,10 @@ base::Value CrostiniDiskInfoToValue(
 }
 }  // namespace
 
-void CrostiniHandler::HandleGetCrostiniSharedUsbDevices(
+void CrostiniHandler::HandleNotifyCrostiniSharedUsbDevicesPageReady(
     const base::ListValue* args) {
   AllowJavascript();
-  CHECK_EQ(1U, args->GetList().size());
-
-  std::string callback_id = args->GetList()[0].GetString();
-
-  chromeos::CrosUsbDetector* detector = chromeos::CrosUsbDetector::Get();
-  if (!detector) {
-    ResolveJavascriptCallback(base::Value(callback_id), base::ListValue());
-    return;
-  }
-
-  ResolveJavascriptCallback(
-      base::Value(callback_id),
-      UsbDevicesToListValue(detector->GetDevicesSharableWithCrostini()));
+  OnUsbDevicesChanged();
 }
 
 void CrostiniHandler::HandleSetCrostiniUsbDeviceShared(

chrome/browser/ui/webui/settings/chromeos/crostini_handler.h

@@ -58,8 +58,9 @@ class CrostiniHandler : public ::settings::SettingsPageUIHandler,
                                    const std::string& path,
                                    bool result,
                                    const std::string& failure_reason);
-  // Returns a list of available USB devices.
-  void HandleGetCrostiniSharedUsbDevices(const base::ListValue* args);
+  // Called when the shared USB devices page is ready.
+  void HandleNotifyCrostiniSharedUsbDevicesPageReady(
+      const base::ListValue* args);
   // Set the share state of a USB device.
   void HandleSetCrostiniUsbDeviceShared(const base::ListValue* args);
   // chromeos::SharedUsbDeviceObserver.

chrome/test/data/webui/settings/chromeos/test_crostini_browser_proxy.js

@@ -9,7 +9,7 @@ class TestCrostiniBrowserProxy extends TestBrowserProxy {
       'requestCrostiniInstallerView',
       'requestRemoveCrostini',
       'getCrostiniSharedPathsDisplayText',
-      'getCrostiniSharedUsbDevices',
+      'notifyCrostiniSharedUsbDevicesPageReady',
       'setCrostiniUsbDeviceShared',
       'removeCrostiniSharedPath',
       'exportCrostiniContainer',
@@ -84,9 +84,10 @@ class TestCrostiniBrowserProxy extends TestBrowserProxy {
   }
 
   /** @override */
-  getCrostiniSharedUsbDevices() {
-    this.methodCalled('getCrostiniSharedUsbDevices');
-    return Promise.resolve(this.sharedUsbDevices);
+  notifyCrostiniSharedUsbDevicesPageReady() {
+    this.methodCalled('notifyCrostiniSharedUsbDevicesPageReady');
+    cr.webUIListenerCallback(
+        'crostini-shared-usb-devices-changed', this.sharedUsbDevices);
   }
 
   /** @override */