Switch to LayoutThemeMobile when emulating mobile device in DevTools.

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 65 matching lines @@
 PassRefPtr<ComputedStyle> ComputedStyle::create()
 {
     return adoptRef(new ComputedStyle());
 }
 
 PassRefPtr<ComputedStyle> ComputedStyle::createInitialStyle()
 {
     return adoptRef(new ComputedStyle(InitialStyle));
 }
 
+void ComputedStyle::clearInitialStyle()

[dgozman, 2016/02/11 18:53:44]

I need some kind of invalidation mechanism which rebuilds initial style created
with DEFINE_STATIC_GLOBAL. I tried to make it least intrusive, but any ideas are
welcome.

[pdr., 2016/02/12 06:36:14]

Can you help me understand why this needs to be rebuilt? Is this just for
tapHighlightColor or is it for more?

Is it okay that this leaks a full computed style every time?

Is this even safe to change? Won't existing pages that have a reference to this
object get very confused?

[dgozman, 2016/02/19 19:15:16]

I'm only aware of tapHighlightColor, but perhaps something may arise in the
future.
I could try to solve this differently - e.g. by invalidating tapHighlightColor
specifically.
It should not, |holder| below takes care of that.
ComputedStyle is refcounted so all objects holding a raw pointer to it should be
stack allocated.
https://code.google.com/p/chromium/codesearch#search/&q=ComputedStyle%5C*%5B%...

+{
+    ComputedStyle** pointer = initialStylePointer();
+    if (!*pointer)
+        return;
+    RefPtr<ComputedStyle> holder = adoptRef(*pointer);
+    {
+        LEAK_SANITIZER_DISABLED_SCOPE;
+        *pointer = createInitialStyle().leakRef();
+    }
+}
+
 PassRefPtr<ComputedStyle> ComputedStyle::createAnonymousStyleWithDisplay(const ComputedStyle& parentStyle, EDisplay display)
 {
     RefPtr<ComputedStyle> newStyle = ComputedStyle::create();
     newStyle->inheritFrom(parentStyle);
     newStyle->inheritUnicodeBidiFrom(parentStyle);
     newStyle->setDisplay(display);
     return newStyle;
 }
 
 PassRefPtr<ComputedStyle> ComputedStyle::clone(const ComputedStyle& other)
@@ skipping 1748 matching lines @@
     if (!shadowList)
         return false;
     for (size_t i = shadowList->shadows().size(); i--; ) {
         if (shadowList->shadows()[i].color().isCurrentColor())
             return true;
     }
     return false;
 }
 
 } // namespace blink