[system-health] Add full Google Search story to the System Health story sets

tools/perf/page_sets/system_health/searching_stories.py

+# Copyright 2016 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.system_health import system_health_story
+
+
+class SearchGoogleStory(system_health_story.SystemHealthStory):
+  NAME = 'search:portal:google'
+  URL = 'https://www.google.co.uk/'
+
+  _SEARCH_BOX_SELECTOR = 'input[aria-label="Search"]'
+  _RESULT_SELECTOR = '.r > a[href*="wikipedia"]'
+
+  def _DidLoadDocument(self, action_runner):
+    # Click on the search box.
+    action_runner.Wait(1)
+    action_runner.WaitForElement(selector=self._SEARCH_BOX_SELECTOR)
+    action_runner.TapElement(selector=self._SEARCH_BOX_SELECTOR)
+
+    # Submit search query.
+    action_runner.Wait(1)
+    action_runner.EnterText('what is science')
+    action_runner.Wait(0.5)
+    action_runner.PressKey('Return')
+
+    # Scroll to the Wikipedia result.
+    action_runner.WaitForElement(selector=self._RESULT_SELECTOR)
+    action_runner.Wait(1)
+    # TODO(petrcermak): Turn this into a proper Telemetry API (ScrollToElement).
+    result_visible_expression = ('''
+        (function() {
+          var resultElem = document.querySelector(\'%s\');
+          var boundingRect = resultElem.getBoundingClientRect();
+          return boundingRect.bottom >= window.innerHeight
+        })()''' % self._RESULT_SELECTOR)
+    while action_runner.EvaluateJavaScript(result_visible_expression):
+      action_runner.RepeatableBrowserDrivenScroll(y_scroll_distance_ratio=0.75,
+                                                  prevent_fling=False)
+      action_runner.Wait(0.2)
+
+    # Click on the Wikipedia result.
+    action_runner.Wait(1)
+    action_runner.TapElement(selector=self._RESULT_SELECTOR)
+    action_runner.tab.WaitForDocumentReadyStateToBeComplete()