Delete selection gap code.

third_party/WebKit/Source/core/layout/LayoutBR.cpp

 /**
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2006 Apple Computer, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 27 matching lines @@
     : LayoutText(node, newlineString())
 {
 }
 
 LayoutBR::~LayoutBR()
 {
 }
 
 LayoutRect LayoutBR::selectionRectForPaintInvalidation(const LayoutBoxModelObject* paintInvalidationContainer) const
 {
-    if (!RuntimeEnabledFeatures::selectionPaintingWithoutSelectionGapsEnabled())

[chrishtr, 2016/01/28 22:06:22]

Why was this a negation of the feature when early-returning?

[wkorman, 2016/01/28 22:54:32]

This code was added as part of the new selection gap behavior:

https://codereview.chromium.org/1350973003

Previously line breaks did not need any special selection gap related
invalidation since they did not actually paint anything.

So, it was easiest to just do this early return with an empty rect when the new
behavior was not enabled.

-        return LayoutRect();
-
     // Although line breaks contain no actual text, if we're selected we need
     // to return a rect that includes space to illustrate a newline.
     return LayoutText::selectionRectForPaintInvalidation(paintInvalidationContainer);
 }
 
 int LayoutBR::lineHeight(bool firstLine) const
 {
     const ComputedStyle& style = styleRef(firstLine && document().styleEngine().usesFirstLineRules());
     return style.computedLineHeight();
 }
@@ skipping 12 matching lines @@
 {
     return 1;
 }
 
 PositionWithAffinity LayoutBR::positionForPoint(const LayoutPoint&)
 {
     return createPositionWithAffinity(0);
 }
 
 } // namespace blink