Generate diffs for fields in ComputedStyle that use their public getters

third_party/WebKit/Source/core/style/ComputedStyle.cpp

 /*
  * Copyright (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights
  * reserved.
  * Copyright (C) 2011 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
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 568 matching lines @@
 
 bool ComputedStyle::DiffNeedsFullLayoutAndPaintInvalidation(
     const ComputedStyle& other) const {
   // FIXME: Not all cases in this method need both full layout and paint
   // invalidation.
   // Should move cases into DiffNeedsFullLayout() if
   // - don't need paint invalidation at all;
   // - or the layoutObject knows how to exactly invalidate paints caused by the
   //   layout change instead of forced full paint invalidation.
 
-  if (surround_data_.Get() != other.surround_data_.Get()) {
-    // If our border widths change, then we need to layout. Other changes to
-    // borders only necessitate a paint invalidation.
-    if (!(BorderWidthEquals(BorderLeftWidth(), other.BorderLeftWidth())) ||

[shend, 2017/05/12 06:59:17]

The generated code does == directly, instead of BorderWidthEquals which calls
WidthToFixedPoint. Is there a change in behaviour here?

[nainar, 2017/05/12 07:07:47]

So I checked before I landed my CL splitting border-*-width the diffing was the
same as the generated code:
https://codereview.chromium.org/2861773004/diff/100001/third_party/WebKit/Sou...

-        !(BorderWidthEquals(BorderTopWidth(), other.BorderTopWidth())) ||
-        !(BorderWidthEquals(BorderBottomWidth(), other.BorderBottomWidth())) ||
-        !(BorderWidthEquals(BorderRightWidth(), other.BorderRightWidth())))
-      return true;
-  }
-
   if (ComputedStyleBase::DiffNeedsFullLayoutAndPaintInvalidation(other))
     return true;
 
   if (rare_non_inherited_data_.Get() != other.rare_non_inherited_data_.Get()) {
     if (rare_non_inherited_data_->appearance_ !=
             other.rare_non_inherited_data_->appearance_ ||
         rare_non_inherited_data_->margin_before_collapse !=
             other.rare_non_inherited_data_->margin_before_collapse ||
         rare_non_inherited_data_->margin_after_collapse !=
             other.rare_non_inherited_data_->margin_after_collapse ||
@@ skipping 1909 matching lines @@
     if (value < 0)
       fvalue -= 0.5f;
     else
       fvalue += 0.5f;
   }
 
   return RoundForImpreciseConversion<int>(fvalue / zoom_factor);
 }
 
 }  // namespace blink