Bug 1005937 - Make the 'touch-action' CSS property apply to all elements except non-replaced inline elements and table rows, columns, and row/column-groups. r=dbaron

widget/xpwidgets/ContentHelper.cpp

@@ -18,18 +18,27 @@ namespace widget {
 uint32_t
 ContentHelper::GetTouchActionFromFrame(nsIFrame* aFrame)
 {
-  if (!aFrame || !aFrame->GetContent() || !aFrame->GetContent()->GetPrimaryFrame()) {
-    // If frame is invalid or null then return default value.
+  // If aFrame is null then return default value
+  if (!aFrame) {
     return NS_STYLE_TOUCH_ACTION_AUTO;
   }
 
-  if (!aFrame->IsFrameOfType(nsIFrame::eSVG) && !aFrame->IsFrameOfType(nsIFrame::eBlockFrame)) {
-    // Since touch-action property can be applied to only svg and block-level
-    // elements we ignore frames of other types.
+  // The touch-action CSS property applies to: all elements except:
+  // non-replaced inline elements, table rows, row groups, table columns, and column groups
+  bool isNonReplacedInlineElement = aFrame->IsFrameOfType(nsIFrame::eLineParticipant);
+  if (isNonReplacedInlineElement) {
     return NS_STYLE_TOUCH_ACTION_AUTO;
   }
 
-  return (aFrame->GetContent()->GetPrimaryFrame()->StyleDisplay()->mTouchAction);
+  const nsStyleDisplay* disp = aFrame->StyleDisplay();
+  bool isTableElement = disp->IsInnerTableStyle() &&
+                        disp->mDisplay != NS_STYLE_DISPLAY_TABLE_CELL &&
+                        disp->mDisplay != NS_STYLE_DISPLAY_TABLE_CAPTION;
+  if (isTableElement) {
+    return NS_STYLE_TOUCH_ACTION_AUTO;
+  }
+
+  return disp->mTouchAction;
 }
 
 void