Refactored the abstraction layer to address prerendered pages on Safari caused by leaky abstraction

webrequest.js

Index: webrequest.js
===================================================================
--- a/webrequest.js
+++ b/webrequest.js
@@ -46,9 +46,9 @@
   }
 });
 
-function onBeforeRequest(url, type, tab, frame)
+function onBeforeRequest(url, type, page, frame)
 {
-  if (isFrameWhitelisted(tab, frame))
+  if (isFrameWhitelisted(page, frame))
     return true;
 
   var docDomain = extractHostFromURL(frame.url);
@@ -59,7 +59,7 @@
     isThirdParty(extractHostFromURL(url), docDomain)
   );
 
-  FilterNotifier.triggerListeners("filter.hitCount", filter, 0, 0, tab);
+  FilterNotifier.triggerListeners("filter.hitCount", filter, 0, 0, page);
   return !(filter instanceof BlockingFilter);
 }
 
@@ -75,8 +75,8 @@
     if (details.type != "main_frame" && details.type != "sub_frame")
       return;
 
-    var tab = new Tab({id: details.tabId});
-    var frame = new Frame({id: details.frameId, tab: tab});
+    var page = new ext.Page({id: details.tabId});
+    var frame = new ext.Frame({frameId: details.frameId, tabId: details.tabId});
 
     if (frame.url != details.url)
       return;
@@ -85,7 +85,7 @@
     {
       var header = details.responseHeaders[i];
       if (header.name.toLowerCase() == "x-adblock-key" && header.value)
-        processKeyException(header.value, tab, frame);
+        processKeyException(header.value, page, frame);
     }
   }