Fix "unreachable code" warnings (MSVC warning 4702) in Blink.

Source/core/rendering/RenderBox.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 335 matching lines @@
     return snapSizeToPixel(offsetWidth(), x() + clientLeft());
 }
 
 int RenderBox::pixelSnappedOffsetHeight() const
 {
     return snapSizeToPixel(offsetHeight(), y() + clientTop());
 }
 
 bool RenderBox::canDetermineWidthWithoutLayout() const
 {
-    // FIXME: This optimization is incorrect as written.
-    // We need to be able to opt-in to this behavior only when
-    // it's guarentted correct.
-    // Until then disabling this optimization to be safe.
+    // FIXME: Remove function and callers.
     return false;
-
-    // FIXME: There are likely many subclasses of RenderBlockFlow which
-    // cannot determine their layout just from style!
-    // Perhaps we should create a "PlainRenderBlockFlow"
-    // and move this optimization there?
-    if (!isRenderBlockFlow()
-        // Flexbox items can be expanded beyond their width.
-        || isFlexItemIncludingDeprecated()
-        // Table Layout controls cell size and can expand beyond width.
-        || isTableCell())
-        return false;
-
-    RenderStyle* style = this->style();
-    return style->width().isFixed()
-        && style->minWidth().isFixed()
-        && (style->maxWidth().isUndefined() || style->maxWidth().isFixed())
-        && style->paddingLeft().isFixed()
-        && style->paddingRight().isFixed()
-        && style->boxSizing() == CONTENT_BOX;
 }
 
 LayoutUnit RenderBox::fixedOffsetWidth() const
 {
     ASSERT(canDetermineWidthWithoutLayout());
 
     RenderStyle* style = this->style();
 
     LayoutUnit width = std::max(LayoutUnit(style->minWidth().value()), LayoutUnit(style->width().value()));
     if (style->maxWidth().isFixed())
@@ skipping 4315 matching lines @@
         return 0;
 
     if (!layoutState && !flowThreadContainingBlock())
         return 0;
 
     RenderBlock* containerBlock = containingBlock();
     return containerBlock->offsetFromLogicalTopOfFirstPage() + logicalTop();
 }
 
 } // namespace WebCore