Issue 5781 - Merge messages for regular and emulated element hiding filters

lib/cssInjection.js

Index: lib/cssInjection.js
===================================================================
--- a/lib/cssInjection.js
+++ b/lib/cssInjection.js
@@ -21,6 +21,7 @@
 
 const {RegExpFilter} = require("filterClasses");
 const {ElemHide} = require("elemHide");
+const {ElemHideEmulation} = require("elemHideEmulation");
 const {checkWhitelisted} = require("whitelisting");
 const {extractHostFromFrame} = require("url");
 const {port} = require("messaging");
@@ -43,6 +44,7 @@
 port.on("elemhide.getSelectors", (msg, sender) =>
 {
   let selectors = [];
+  let emulatedPatterns = [];
   let trace = devtools && devtools.hasPanel(sender.page);
   let inject = !userStyleSheetsSupported;
 
@@ -50,18 +52,23 @@
                         RegExpFilter.typeMap.DOCUMENT |
                         RegExpFilter.typeMap.ELEMHIDE))
   {
+    let hostname = extractHostFromFrame(sender.frame);
     let specificOnly = checkWhitelisted(sender.page, sender.frame,
                                         RegExpFilter.typeMap.GENERICHIDE);
+
     selectors = ElemHide.getSelectorsForDomain(
-      extractHostFromFrame(sender.frame),
+      hostname,
       specificOnly ? ElemHide.SPECIFIC_ONLY : ElemHide.ALL_MATCHING
     );
+
+    for (let filter of ElemHideEmulation.getRulesForDomain(hostname))
+      emulatedPatterns.push({selector: filter.selector, text: filter.text});
   }
 
   if (!inject && selectors.length > 0)
     hideElements(sender.page.id, sender.frame.id, selectors);
 
-  let response = {trace, inject};
+  let response = {trace, inject, emulatedPatterns};
   if (trace || inject)
     response.selectors = selectors;