Issue 5695 - Use tabs.insertCSS if extensionTypes.CSSOrigin exists

include.preload.js

Index: include.preload.js
===================================================================
--- a/include.preload.js
+++ b/include.preload.js
@@ -436,17 +436,17 @@
       ).join(", ");
       this.style.sheet.insertRule(selector + "{display: none !important;}",
                                   this.style.sheet.cssRules.length);
     }
   },
 
   addSelectors(selectors, filters)
   {
-    if (!selectors || selectors.length == 0)
+    if (selectors.length == 0)
       return;
 
     if (this.inject)
     {
       // Insert the style rules inline if we have been instructed by the
       // background page to do so. This is usually the case, except on platforms
       // that do support user stylesheets via the chrome.tabs.insertCSS API
       // (Firefox 53 onwards for now and possibly Chrome in the near future).
@@ -496,20 +496,23 @@
         this.style.parentElement.removeChild(this.style);
       this.style = null;
 
       if (response.trace)
         this.tracer = new ElementHidingTracer();
 
       this.inject = response.inject;
 
-      if (this.inject)
-        this.addSelectors(response.selectors);
-      else if (this.tracer)
-        this.tracer.addSelectors(response.selectors);
+      if (response.selectors)

[Manish Jethani, 2017/09/17 13:51:38]

Check for the existence of response.selectors since it will be missing if there
are no selectors.

+      {
+        if (this.inject)
+          this.addSelectors(response.selectors);
+        else if (this.tracer)
+          this.tracer.addSelectors(response.selectors);
+      }
 
       this.elemHideEmulation.apply();
     });
   }
 };
 
 if (document instanceof HTMLDocument)
 {