Issue 6957 - Skip selector lookup for unknown domains

lib/elemHide.js

Index: lib/elemHide.js
===================================================================
--- a/lib/elemHide.js
+++ b/lib/elemHide.js
@@ -353,21 +353,24 @@
 
   /**
    * Generates a style sheet for a given domain based on the current set of
    * filters.
    *
    * @param {string} domain The domain.
    * @param {boolean} [specificOnly=false] Whether selectors from generic
    *   filters should be included.
+   * @param {boolean} [includeSelectors=false] Whether the return value should
+   *   include a separate list of selectors.
    *
    * @returns {ElemHideStyleSheet} An object containing the CSS code and the
    *   list of selectors.
    */
-  generateStyleSheetForDomain(domain, specificOnly = false)
+  generateStyleSheetForDomain(domain, specificOnly = false,
+                              includeSelectors = false)
   {
     let code = null;
     let selectors = null;
 
     if (domain[domain.length - 1] == ".")
       domain = domain.replace(/\.+$/, "");
 
     domain = domain.toLowerCase();
@@ -376,24 +379,34 @@
     {
       selectors = getConditionalSelectors(domain, true);
       code = createStyleSheet(selectors);
     }
     else
     {
       let knownSuffix = getKnownSuffix(domain);
 
-      selectors = getConditionalSelectors(knownSuffix, false);
-      code = knownSuffix == "" ? getCommonStyleSheet() :
-               (getDefaultStyleSheet() + createStyleSheet(selectors));
+      if (includeSelectors)
+      {
+        selectors = getConditionalSelectors(knownSuffix, false);
+        code = knownSuffix == "" ? getCommonStyleSheet() :
+                 (getDefaultStyleSheet() + createStyleSheet(selectors));
 
-      selectors = getUnconditionalSelectors().concat(selectors);
+        selectors = getUnconditionalSelectors().concat(selectors);
+      }
+      else
+      {
+        code = knownSuffix == "" ? getCommonStyleSheet() :
+                 (getDefaultStyleSheet() +
+                  createStyleSheet(getConditionalSelectors(knownSuffix,
+                                                           false)));
+      }
     }
 
-    return {code, selectors};
+    return {code, selectors: includeSelectors ? selectors : null};
   }
 };
 
 /**
  * Splits a list of selectors into groups determined by the value of
  * <code>{@link selectorGroupSize}</code>.
  *
  * @param {Array.<string>} selectors