Backed out changeset 5a4a5749f8dc (bug 1767262) for causing wpt failures.

layout/generic/nsBlockFrame.cpp

@@ -1262,11 +1262,6 @@ static bool IsLineClampItem(const ReflowInput& aReflowInput) {
 void nsBlockFrame::Reflow(nsPresContext* aPresContext, ReflowOutput& aMetrics,
                           const ReflowInput& aReflowInput,
                           nsReflowStatus& aStatus) {
-  if (GetInFlowParent() && GetInFlowParent()->IsContentHiddenForLayout()) {
-    FinishAndStoreOverflow(&aMetrics, aReflowInput.mStyleDisplay);
-    return;
-  }
-
   MarkInReflow();
   DO_GLOBAL_REFLOW_COUNT("nsBlockFrame");
   DISPLAY_REFLOW(aPresContext, this, aReflowInput, aMetrics, aStatus);
@@ -2536,10 +2531,6 @@ static bool LinesAreEmpty(const nsLineList& aList) {
 }
 
 void nsBlockFrame::ReflowDirtyLines(BlockReflowState& aState) {
-  if (IsContentHiddenForLayout()) {
-    return;
-  }
-
   bool keepGoing = true;
   bool repositionViews = false;  // should we really need this?
   bool foundAnyClears = aState.mFloatBreakType != StyleClear::None;