Removing Page.WaitToLoad and update all pagesets to use explicit wait actions

tools/perf/page_sets/key_mobile_sites.json

 {
   "description": "Key mobile sites",
   "archive_data_file": "../data/key_mobile_sites.json",
   "credentials_path": "../data/credentials.json",
   "user_agent_type": "mobile",
   "smoothness": { "action": "scroll" },
   "pages": [
     {
       "url": "http://www.androidpolice.com/2012/10/03/rumor-evidence-mounts-that-an-lg-optimus-g-nexus-is-coming-along-with-a-nexus-phone-certification-program/",
       "why": "crbug.com/242544"
     },
     {
       "url": "http://nytimes.com/",
       "why": "Top news site"
     },
     {
       "url": "http://iphone.capitolvolkswagen.com/index.htm#new-inventory_p_2Fsb-new_p_2Ehtm_p_3Freset_p_3DInventoryListing",
       "why": "Typical mobile business site",
-      "wait_for_element_with_text": "Next 35"
+      "navigate_steps": [
+        { "action": "navigate" },
+        { "action": "wait", "condition": "element", "text": "Next 35" }
+      ]
     },
     {
       "url": "http://gsp.ro",
       "why": "crbug.com/149958"
     },
     {
       "url": "http://cuteoverload.com",
       "why": "Image-heavy site"
     },
     {
       "url": "http://theverge.com",
       "why": "Top tech blog"
     },
     {
       "url": "http://www.theverge.com/2012/10/28/3568746/amazon-7-inch-fire-hd-ipad-mini-ad-ballsy",
       "why": "Top tech blog",
-      "wait_for_javascript_expression": "window.Chorus !== undefined && window.Chorus.Comments !== undefined && window.Chorus.Comments.Json !== undefined && (window.Chorus.Comments.loaded || window.Chorus.Comments.Json.load_comments())"
+      "navigate_steps": [
+        { "action": "navigate" },
+        { "action": "wait", "javascript": "window.Chorus !== undefined && window.Chorus.Comments !== undefined && window.Chorus.Comments.Json !== undefined && (window.Chorus.Comments.loaded || window.Chorus.Comments.Json.load_comments())" }
+      ]
     },
     {
       "url": "http://www.cnn.com/2012/10/03/politics/michelle-obama-debate/index.html",
       "why": "Top news site",
-      "wait_seconds": 8
+      "navigate_steps": [
+        { "action": "navigate" },
+        { "action": "wait", "seconds": 8 }
+      ]
     },
     {
       "url": "http://digg.com",
       "why": "Top tech site"
     },
     {
       "url": "https://www.google.com/#hl=en&q=barack+obama",
       "why": "Top Google property; a Google tab is often open"
     },
     {
       "url": "https://plus.google.com/app/basic/110031535020051778989/posts?source=apppromo",
       "why": "Social; top Google property; Public profile; infinite scrolls",
       "smoothness": {
         "action": "scroll",
         "scroll_is_infinite": true
       }
     },
     {
       "url": "https://facebook.com/barackobama",
       "why": "#1 (Alexa global)",
-      "wait_for_javascript_expression": "document.getElementById('timelineBody') !== null"
+      "navigate_steps": [
+        { "action": "navigate" },
+        { "action": "wait", "javascript": "document.getElementById('timelineBody') !== null" }
+      ]
     },
     {
       "url": "http://m.youtube.com/watch?v=9hBpF_Zj4OA",
       "why": "#3 (Alexa global)",
-      "wait_for_javascript_expression": "document.getElementById('paginatortarget') !== null"
+      "navigate_steps": [
+        { "action": "navigate"},
+        { "action": "wait", "javascript": "document.getElementById('paginatortarget') !== null"}
+      ]
     },
     {
       "name": "Blogger",
       "url": "http://googlewebmastercentral.blogspot.com/",
       "why": "#11 (Alexa global), google property; some blogger layouts have infinite scroll but more interesting"
     },
     {
       "name": "Wordpress",
       "url": "http://en.blog.wordpress.com/2012/09/04/freshly-pressed-editors-picks-for-august-2012/",
       "why": "#18 (Alexa global), Picked an interesting post"
     },
     {
       "name": "LinkedIn",
       "url": "https://www.linkedin.com/in/linustorvalds",
       "why": "#12 (Alexa global),Public profile",
-      "post_navigate_javascript_to_execute": "getAppJs.noApp();",
-      "wait_for_javascript_expression": "document.getElementById('profile-view-scroller') !== null"
+      "navigate_steps": [
+        { "action": "navigate" },
+        { "action": "javascript", "expression": "getAppJs.noApp();" },
+        { "action": "wait", "javascript": "document.getElementById('profile-view-scroller') !== null" }
+      ]
     },
     {
       "name": "Wikipedia (1 tab)",
       "url": "http://en.wikipedia.org/wiki/Wikipedia",
       "why": "#6 (Alexa) most visited worldwide, picked an interesting page"
     },
     {
       "disabled": "Forbidden (Rate Limit Exceeded)",
       "name": "Twitter",
       "url": "http://twitter.com/katyperry",
@@ skipping 39 matching lines @@
       "why": "#1 Alexa sports"
     },
     {
       "url": "http://techcrunch.com",
       "why": "Top tech blog"
     },
     {
       "url": "https://mail.google.com/mail/",
       "why": "productivity, top google properties",
       "credentials": "google",
-      "wait_for_element_with_text": "Inbox",
+      "navigate_steps": [
+        { "action": "navigate" },
+        { "action": "wait", "condition": "element", "text": "Inbox" }
+      ],
       "smoothness": {
         "action": "scroll",
         "scrollable_element_function": "function(callback) { callback(document.getElementById('views').childNodes[1].firstChild); }"
       }
     },
     {
       "url": "http://mlb.mlb.com/index.jsp",
       "why": "#6 Alexa sports"
     },
     {
@@ skipping 32 matching lines @@
       "url": "http://www.reddit.com/r/programming/comments/1g96ve",
       "why": "#5 Alexa news"
     },
     {
       "url": "http://www.boingboing.net",
       "why": "Problematic use of fixed position elements"
     },
     {
       "url": "http://groupcloned.com",
       "why": "crbug.com/172906",
-      "wait_for_javascript_expression": "document.getElementById('element-19') !== null && document.getElementById('element-19').contentDocument.getElementById('element-22') !== null && document.getElementById('element-19').contentDocument.getElementsByClassName('container list-item gc-list-item stretched').length !== 0",
-      "wait_seconds": 5,
+      "navigate_steps": [
+        { "action": "navigate" },
+        { "action": "wait", "seconds": 5 },
+        { "action": "wait", "javascript": "document.getElementById('element-19') !== null && document.getElementById('element-19').contentDocument.getElementById('element-22') !== null && document.getElementById('element-19').contentDocument.getElementsByClassName('container list-item gc-list-item stretched').length !== 0" }
+      ],
       "smoothness": {
         "action": "scroll",
         "scroll_requires_touch": true,
         "remaining_scroll_distance_function": "function() { return Math.max(0, 1250 + document.getElementById('element-19').contentDocument.getElementById('element-22').getBoundingClientRect().top); }"
       }
     },
     {
       "disabled": "Doesn't scroll; crbug.com/249736",
       "url": "http://forecast.io",
       "why": "crbug.com/231413"
     }
   ]
 }