Bug 1520611 - Add pivot prune prefilter, use it in jsat. r=yzen

Differential Revision: https://phabricator.services.mozilla.com/D16742

--HG--
extra : moz-landing-system : lando

accessible/base/nsAccessiblePivot.cpp

@@ -847,6 +847,11 @@ nsresult RuleCache::ApplyFilter(Accessible* aAccessible, uint16_t* aResult) {
   if (mPreFilter) {
     uint64_t state = aAccessible->State();
 
+    if ((nsIAccessibleTraversalRule::PREFILTER_PLATFORM_PRUNED & mPreFilter) &&
+        nsAccUtils::MustPrune(aAccessible)) {
+      *aResult |= nsIAccessibleTraversalRule::FILTER_IGNORE_SUBTREE;
+    }
+
     if ((nsIAccessibleTraversalRule::PREFILTER_INVISIBLE & mPreFilter) &&
         (state & states::INVISIBLE))
       return NS_OK;
@@ -879,5 +884,10 @@ nsresult RuleCache::ApplyFilter(Accessible* aAccessible, uint16_t* aResult) {
     if (!matchesRole) return NS_OK;
   }
 
-  return mRule->Match(ToXPC(aAccessible), aResult);
+  uint16_t matchResult = nsIAccessibleTraversalRule::FILTER_IGNORE;
+  nsresult rv = mRule->Match(ToXPC(aAccessible), &matchResult);
+  if (NS_SUCCEEDED(rv)) {
+    *aResult |= matchResult;
+  }
+  return rv;
 }

accessible/interfaces/nsIAccessiblePivot.idl

@@ -227,11 +227,11 @@ interface nsIAccessibleTraversalRule : nsISupports
   const unsigned short FILTER_IGNORE_SUBTREE = 0x2;
 
   /* Pre-filters */
-  const unsigned long PREFILTER_INVISIBLE     = 0x00000001;
-  const unsigned long PREFILTER_OFFSCREEN     = 0x00000002;
-  const unsigned long PREFILTER_NOT_FOCUSABLE = 0x00000004;
-  const unsigned long PREFILTER_TRANSPARENT   = 0x00000008;
-
+  const unsigned long PREFILTER_INVISIBLE         = 0x00000001;
+  const unsigned long PREFILTER_OFFSCREEN         = 0x00000002;
+  const unsigned long PREFILTER_NOT_FOCUSABLE     = 0x00000004;
+  const unsigned long PREFILTER_TRANSPARENT       = 0x00000008;
+  const unsigned long PREFILTER_PLATFORM_PRUNED   = 0x00000010;
   /**
    * Pre-filter bitfield to filter out obviously ignorable nodes and lighten
    * the load on match().

accessible/jsat/Traversal.jsm

@@ -166,15 +166,15 @@ var gSimpleMatchFunc = function gSimpleMatchFunc(aAccessible) {
 
 var gSimplePreFilter = Prefilters.DEFUNCT |
   Prefilters.INVISIBLE |
-  Prefilters.TRANSPARENT;
+  Prefilters.TRANSPARENT |
+  Prefilters.PLATFORM_PRUNED;
 
 var TraversalRules = { // jshint ignore:line
   Simple: new BaseTraversalRule(gSimpleTraversalRoles, gSimpleMatchFunc),
 
   SimpleOnScreen: new BaseTraversalRule(
     gSimpleTraversalRoles, gSimpleMatchFunc,
-    Prefilters.DEFUNCT | Prefilters.INVISIBLE |
-    Prefilters.TRANSPARENT | Prefilters.OFFSCREEN),
+    gSimplePreFilter | Prefilters.OFFSCREEN),
 
   Anchor: new BaseTraversalRule(
     [Roles.LINK],

accessible/tests/mochitest/jsat/test_traversal.html

@@ -117,13 +117,13 @@
                               "4. Standard Lisp", "link-0", " Lisp",
                               "checkbox-1-5", " LeLisp", "• JavaScript",
                               "heading-5", "image-1", "image-2", "image-3",
-                              "Not actually an image", "link-1", "anchor-1",
-                              "link-2", "anchor-2", "link-3", "3", "1", "4",
-                              "1", "Sunday", "M", "Week 1", "3", "4", "7", "2",
-                              "5 8", "gridcell4", "Just an innocuous separator",
+                              "link-1", "anchor-1", "link-2", "anchor-2",
+                              "link-3", "3", "1", "4", "1", "Sunday", "M",
+                              "Week 1", "3", "4", "7", "2", "5 8", "gridcell4",
                               "Dirty Words", "Meaning", "Mud", "Wet Dirt",
-                              "Dirt", "Messy Stuff", "statusbar-1", "statusbar-2",
-                              "switch-1", "This is a MathML formula ", "math-1",
+                              "Dirt", "Messy Stuff", "statusbar-1",
+                              "statusbar-2", "switch-1",
+                              "This is a MathML formula ", "math-1",
                               "with some text after."]);
 
       queueTraversalSequence(gQueue, docAcc, TraversalRules.Landmark, null,