Reland^2 "[perf] Add browse:media:tumblr:2018 system health story"

Original change's description:
> [perf] Add browse:media:tumblr:2018 system health story
>
> This also add a login helper for tumblr and updates credentials.json
>
> Bug: 878390
> Change-Id: Iba56faf550cb638692899326b217347e04be9932
> Reviewed-on: https://chromium-review.googlesource.com/c/1256883
> Reviewed-by: Juan Antonio Navarro Pérez <perezju@chromium.org>
> Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#596763}

Change-Id: I45d738bf10b7fcc72a1d032785d4eba2727b5363
Reviewed-on: https://chromium-review.googlesource.com/c/1277789Reviewed-by: Ned Nguyen <nednguyen@google.com>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#599252}

tools/perf/page_sets/data/credentials.json.sha1

-62bb07f739452c44b3618b9b3f3de6251bf73322
+6840cad1ab0a693cc418aadd60718c195eb48445
\ No newline at end of file

tools/perf/page_sets/data/system_health_desktop.json

@@ -12,6 +12,9 @@
         "browse:media:tumblr": {
             "DEFAULT": "system_health_desktop_036.wprgo"
         },
+        "browse:media:tumblr:2018": {
+            "DEFAULT": "system_health_desktop_55cb9dd713.wprgo"
+        },
         "browse:media:youtube": {
             "DEFAULT": "system_health_desktop_026.wprgo",
             "linux": "system_health_desktop_026.wprgo",

tools/perf/page_sets/data/system_health_desktop_55cb9dd713.wprgo.sha1

+55cb9dd71364f014e51f4ed50207ac91820a555d
\ No newline at end of file

tools/perf/page_sets/login_helpers/tumblr_login.py

+# Copyright 2018 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.
+
+from page_sets.login_helpers import login_utils
+
+
+def LoginDesktopAccount(action_runner, credential,
+                 credentials_path=login_utils.DEFAULT_CREDENTIAL_PATH):
+  """Logs in into a Tumblr account."""
+
+  account_name, password = login_utils.GetAccountNameAndPassword(
+      credential, credentials_path=credentials_path)
+
+  action_runner.Navigate('https://www.tumblr.com/login')
+  login_utils.InputWithSelector(
+      action_runner, account_name, 'input[type=email]')
+
+  next_button = '.signup_determine_btn'
+  enter_password_button = '.forgot_password_link'
+  action_runner.WaitForElement(selector=next_button)
+  action_runner.ClickElement(selector=next_button)
+  action_runner.Wait(1)
+  action_runner.WaitForElement(selector=enter_password_button)
+  action_runner.ClickElement(selector=enter_password_button)
+  action_runner.Wait(1)
+  login_utils.InputWithSelector(
+      action_runner, password, 'input[type=password]')
+  action_runner.Wait(1)
+  action_runner.WaitForElement(selector=next_button)
+  action_runner.ClickElement(selector=next_button)

tools/perf/page_sets/system_health/browsing_stories.py

@@ -15,6 +15,7 @@ from page_sets.system_health import system_health_story
 
 from page_sets.login_helpers import facebook_login
 from page_sets.login_helpers import pinterest_login
+from page_sets.login_helpers import tumblr_login
 
 from telemetry.util import js_template
 
@@ -592,6 +593,28 @@ class TumblrDesktopStory(_MediaBrowsingStory):
     action_runner.MouseClick(selector='#tumblr_lightbox_center_image')
     action_runner.Wait(1)  # To make browsing more realistic.
 
+
+class TumblrDesktopStory2018(_MediaBrowsingStory):
+  NAME = 'browse:media:tumblr:2018'
+  URL = 'https://tumblr.com/search/gifs'
+  ITEM_SELECTOR = '.post_media'
+  IS_SINGLE_PAGE_APP = True
+  ITEMS_TO_VISIT = 8
+  INCREMENT_INDEX_AFTER_EACH_ITEM = True
+  SUPPORTED_PLATFORMS = platforms.DESKTOP_ONLY
+  TAGS = [story_tags.YEAR_2018]
+
+  def _Login(self, action_runner):
+    tumblr_login.LoginDesktopAccount(action_runner, 'tumblr')
+    action_runner.Wait(3)
+
+  def _ViewMediaItem(self, action_runner, index):
+    super(TumblrDesktopStory2018, self)._ViewMediaItem(action_runner, index)
+    action_runner.WaitForElement(selector='#tumblr_lightbox')
+    action_runner.MouseClick(selector='#tumblr_lightbox')
+    action_runner.Wait(1)  # To make browsing more realistic.
+
+
 class PinterestDesktopStory(_MediaBrowsingStory):
   NAME = 'browse:media:pinterest'
   URL = 'https://pinterest.com'