Bug 1076657 pt 1 - Fix ContentEventHandler::OnQueryTextRect for vertical textframes. r=smontagu

dom/events/ContentEventHandler.cpp

@@ -942,8 +942,13 @@ ContentEventHandler::OnQueryTextRect(WidgetQueryContentEvent* aEvent)
   nsPoint ptOffset;
   firstFrame->GetPointFromOffset(nodeOffset, &ptOffset);
   // minus 1 to avoid creating an empty rect
-  rect.x += ptOffset.x - 1;
-  rect.width -= ptOffset.x - 1;
+  if (firstFrame->GetWritingMode().IsVertical()) {
+    rect.y += ptOffset.y - 1;
+    rect.height -= ptOffset.y - 1;
+  } else {
+    rect.x += ptOffset.x - 1;
+    rect.width -= ptOffset.x - 1;
+  }
 
   // get the ending frame
   nodeOffset = range->EndOffset();
@@ -984,7 +989,11 @@ ContentEventHandler::OnQueryTextRect(WidgetQueryContentEvent* aEvent)
   // get the ending frame rect
   lastFrame->GetPointFromOffset(nodeOffset, &ptOffset);
   // minus 1 to avoid creating an empty rect
-  frameRect.width -= lastFrame->GetRect().width - ptOffset.x - 1;
+  if (lastFrame->GetWritingMode().IsVertical()) {
+    frameRect.height -= lastFrame->GetRect().height - ptOffset.y - 1;
+  } else {
+    frameRect.width -= lastFrame->GetRect().width - ptOffset.x - 1;
+  }
 
   if (firstFrame == lastFrame) {
     rect.IntersectRect(rect, frameRect);