Unprefix the CSS 'filter' property

third_party/WebKit/Source/core/paint/SVGPaintContext.cpp

 /*
  * Copyright (C) 2007, 2008 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Google, Inc.  All rights reserved.
  * Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
  * Copyright (C) Research In Motion Limited 2009-2010. 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 59 matching lines @@
     SVGResources* resources = SVGResourcesCache::cachedResourcesForLayoutObject(&m_object);
 
     // When rendering clip paths as masks, only geometric operations should be included so skip
     // non-geometric operations such as compositing, masking, and filtering.
     if (paintInfo().isRenderingClipPathAsMaskImage()) {
         if (!applyClipIfNecessary(resources))
             return false;
         return true;
     }
 
-    applyCompositingIfNecessary();
+    bool isSVGRoot = m_object.isSVGRoot();
+
+    // Layer takes care of root opacity and blend mode.

[pdr., 2016/06/15 09:50:32]

Can you assert that a layer is present? (Similarly below for filter)

Something like:
if (isSVGRoot) {
    // The PaintLayer will take care of compositing the root.
    DCHECK(m_object.hasLayer());
} else {
    applyCompositingIfNecessary();
}

[fs, 2016/06/15 11:02:43]

Added something along those lines.

[fs, 2016/06/15 22:02:09]

Had to adjust this again, because while "has filter" implies "has layer", "has
layer" does not necessarily imply "has filter"; i.e this is not an equivalence.
Since I don't want to add conditional DCHECKs, are there any particular thing
you'd want me to check here?

[fs, 2016/06/20 10:47:07]

Fixed up to something that passes trybots.

+    if (!isSVGRoot)
+        applyCompositingIfNecessary();
 
     if (!applyClipIfNecessary(resources))
         return false;
 
     if (!applyMaskIfNecessary(resources))
         return false;
 
-    if (!applyFilterIfNecessary(resources))
+    if (!isSVGRoot && !applyFilterIfNecessary(resources))
         return false;
 
     if (!isIsolationInstalled() && SVGLayoutSupport::isIsolationRequired(&m_object))
         m_compositingRecorder = adoptPtr(new CompositingRecorder(paintInfo().context, m_object, SkXfermode::kSrcOver_Mode, 1));
 
     return true;
 }
 
 void SVGPaintContext::applyCompositingIfNecessary()
 {
     ASSERT(!paintInfo().isRenderingClipPathAsMaskImage());
 
-    // Layer takes care of root opacity and blend mode.
-    if (m_object.isSVGRoot())
-        return;
-
     const ComputedStyle& style = m_object.styleRef();
     float opacity = style.opacity();
     WebBlendMode blendMode = style.hasBlendMode() && m_object.isBlendingAllowed() ?
         style.blendMode() : WebBlendModeNormal;
     if (opacity < 1 || blendMode != WebBlendModeNormal) {
         const FloatRect compositingBounds = m_object.paintInvalidationRectInLocalSVGCoordinates();
         m_compositingRecorder = adoptPtr(new CompositingRecorder(paintInfo().context, m_object,
             WebCoreCompositeToSkiaComposite(CompositeSourceOver, blendMode), opacity, &compositingBounds));
     }
 }
@@ skipping 25 matching lines @@
         if (!SVGMaskPainter(*masker).prepareEffect(m_object, paintInfo().context))
             return false;
         m_masker = masker;
     }
     return true;
 }
 
 bool SVGPaintContext::applyFilterIfNecessary(SVGResources* resources)
 {
     if (!resources) {
-        if (m_object.style()->svgStyle().hasFilter())
+        if (m_object.style()->hasFilter())
             return false;
     } else if (LayoutSVGResourceFilter* filter = resources->filter()) {
         m_filterRecordingContext = adoptPtr(new SVGFilterRecordingContext(paintInfo().context));
         m_filter = filter;
         GraphicsContext* filterContext = SVGFilterPainter(*filter).prepareEffect(m_object, *m_filterRecordingContext);
         if (!filterContext)
             return false;
 
         // Because the filter needs to cache its contents we replace the context
         // during filtering with the filter's context.
@@ skipping 61 matching lines @@
     // though.
     // Additionally, it's not really safe/guaranteed to be correct, as
     // something down the paint pipe may want to farther tweak the color
     // filter, which could yield incorrect results. (Consider just using
     // saveLayer() w/ this color filter explicitly instead.)
     paint.setColorFilter(sk_ref_sp(paintInfo.context.colorFilter()));
     return true;
 }
 
 } // namespace blink