[Password Manager] Reduce minimum time for showing the export progress

The "busy exporting" dialog is shown for at least 2 seconds, to avoid
flashing when exporting happens fast. We reduce this time to 1 seconds,
as suggested by UX.

Bug: 789561
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: Ibeb1c3736d914ee1d83814dfdc9d3a902fed1796
Reviewed-on: https://chromium-review.googlesource.com/918562Reviewed-by: Hector Carmona <hcarmona@chromium.org>
Commit-Queue: Christos Froussios <cfroussios@chromium.org>
Cr-Commit-Position: refs/heads/master@{#536973}

chrome/browser/resources/settings/passwords_and_forms_page/passwords_export_dialog.js

@@ -33,7 +33,7 @@ const progressBarDelayMs = 100;
  * The minimum amount of time (ms) that the progress bar will be visible.
  * @type {number}
  */
-const progressBarBlockMs = 2000;
+const progressBarBlockMs = 1000;
 
 Polymer({
   is: 'passwords-export-dialog',
@@ -67,16 +67,16 @@ Polymer({
 
   /**
    * The task that will display the completion of the export, if any. We display
-   * the progress bar for at least 2000ms, therefore, if export finishes
-   * earlier, we cache the result in |delayedProgress_| and this task will
-   * consume it. This is null, unless the task is currently scheduled.
+   * the progress bar for at least |progressBarBlockMs|, therefore, if export
+   * finishes earlier, we cache the result in |delayedProgress_| and this task
+   * will consume it. This is null, unless the task is currently scheduled.
    * @private {?number}
    */
   delayedCompletionToken_: null,
 
   /**
-   * We display the progress bar for at least 2000ms. If progress is achieved
-   * earlier, we store the update here and consume it later.
+   * We display the progress bar for at least |progressBarBlockMs|. If progress
+   * is achieved earlier, we store the update here and consume it later.
    * @private {?PasswordManager.PasswordExportProgress}
    */
   delayedProgress_: null,

chrome/test/data/webui/settings/settings_passwords_section_browsertest.js

@@ -672,7 +672,7 @@ TEST_F('SettingsPasswordSectionBrowserTest', 'uiTests', function() {
     });
 
     // Test the export flow. If exporting is slow, Chrome should show the
-    // in-progress dialog for at least 2000ms.
+    // in-progress dialog for at least 1000ms.
     test('exportFlowSlow', function(done) {
       const exportDialog = createExportPasswordsDialog(passwordManager);
       const progressCallback = passwordManager.progressCallback;
@@ -690,7 +690,7 @@ TEST_F('SettingsPasswordSectionBrowserTest', 'uiTests', function() {
       assertTrue(exportDialog.$.dialog_start.open);
 
       // After 100ms of not having completed, the dialog switches to the
-      // progress bar. Chrome will continue to show the progress bar for 2000ms,
+      // progress bar. Chrome will continue to show the progress bar for 1000ms,
       // despite a completion event.
       mockTimer.tick(99);
       assertTrue(exportDialog.$.dialog_start.open);
@@ -700,8 +700,8 @@ TEST_F('SettingsPasswordSectionBrowserTest', 'uiTests', function() {
           {status: chrome.passwordsPrivate.ExportProgressStatus.SUCCEEDED});
       assertTrue(exportDialog.$.dialog_progress.open);
 
-      // After 2000ms, Chrome will display the completion event.
-      mockTimer.tick(1999);
+      // After 1000ms, Chrome will display the completion event.
+      mockTimer.tick(999);
       assertTrue(exportDialog.$.dialog_progress.open);
       mockTimer.tick(1);
       // On SUCCEEDED the dialog closes completely.