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

tools/perf/page_sets/key_desktop_sites.json

Index: tools/perf/page_sets/key_desktop_sites.json
diff --git a/tools/perf/page_sets/key_desktop_sites.json b/tools/perf/page_sets/key_desktop_sites.json
index 85b05e80734583f4487bb753e397ab4f72b53735..8c3e73d2621d5fcca5b5a4c5b2b5baced66dec33 100644
--- a/tools/perf/page_sets/key_desktop_sites.json
+++ b/tools/perf/page_sets/key_desktop_sites.json
@@ -620,10 +620,10 @@
       "url": "https://mail.google.com/mail/",
       "credentials": "google",
       "scrollable_element_function": "function(callback) { gmonkey.load('2.0', function(api) { callback(api.getScrollableElement()); }); }",
-      "smoothness": {
-        "action": "scroll",
-        "wait_for_javascript_expression": "window.gmonkey !== undefined && document.getElementById('gb') !== null"
-      }
+      "smoothness": [
+        { "action": "scroll"},
+        { "action": "wait", "condition": "javascript", "javascript": "window.gmonkey !== undefined && document.getElementById('gb') !== null"}
+      ]
     },
     {
       "url": "https://www.google.com/calendar/",
@@ -634,19 +634,19 @@
       "url": "https://drive.google.com",
       "credentials": "google",
       "scrollable_element_function": "function(callback) { callback(document.getElementsByClassName('doclistview-list')[0]); }",
-      "smoothness": {
-        "action": "scroll",
-        "wait_for_javascript_expression": "document.getElementsByClassName('doclistview-list').length"
-      }
+      "smoothness": [
+        { "action": "scroll"},
+        { "action": "wait", "condition": "javascript", "javascript": "document.getElementsByClassName('doclistview-list').length"}
+      ]
     },
     {
       "url": "https://docs.google.com/a/google.com/document/d/1XMAtPiVFZfItsMUOYl39v5YA8bcSPe4LDrVO25OdsCU/edit",
       "credentials": "google",
       "scrollable_element_function": "function(callback) { callback(document.getElementsByClassName('kix-appview-editor')[0]); }",
-      "smoothness": {
-        "action": "scroll",
-        "wait_for_javascript_expression": "document.getElementsByClassName('kix-appview-editor').length"
-      }
+      "smoothness": [
+        { "action": "scroll"},
+        { "action": "wait", "condition": "javascript", "javascript": "document.getElementsByClassName('kix-appview-editor').length"}
+      ]
     },
     { "url": "https://maps.google.com" },
     { "url": "http://reader.google.com" },