Forward fill and stroke styles from 2d canvas to canvas filters

third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2DState.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "modules/canvas2d/CanvasRenderingContext2DState.h"
 
 #include "core/css/CSSFontSelector.h"
 #include "core/css/resolver/FilterOperationResolver.h"
 #include "core/css/resolver/StyleBuilder.h"
 #include "core/css/resolver/StyleResolverState.h"
@@ skipping 336 matching lines @@
         return nullptr;
 
     if (!m_resolvedFilter) {
         RefPtr<ComputedStyle> filterStyle = ComputedStyle::create();
         // Must set font in case the filter uses any font-relative units (em, ex)
         filterStyle->setFont(font);
 
         StyleResolverState resolverState(styleResolutionHost->document(), styleResolutionHost, filterStyle.get());
         resolverState.setStyle(filterStyle);
 
-        // TODO(junov): crbug.com/502877 Feed m_fillStyle and m_strokeStyle into FillPaint and
-        // StrokePaint respectively for filters that reference SVG.
         StyleBuilder::applyProperty(CSSPropertyWebkitFilter, resolverState, m_filterValue.get());
         RefPtrWillBeRawPtr<FilterEffectBuilder> filterEffectBuilder = FilterEffectBuilder::create();
+
+        // We can't reuse m_fillPaint and m_strokePaint for the filter, since these incorporate
+        // the global alpha, which isn't applicable here.
+        SkPaint fillPaintForFilter;
+        SkPaint strokePaintForFilter;
+        m_fillStyle->applyToPaint(fillPaintForFilter);
+        m_strokeStyle->applyToPaint(strokePaintForFilter);
+        fillPaintForFilter.setColor(m_fillStyle->paintColor());
+        strokePaintForFilter.setColor(m_strokeStyle->paintColor());
         const double effectiveZoom = 1.0; // Deliberately ignore zoom on the canvas element
-        filterEffectBuilder->build(styleResolutionHost, filterStyle->filter(), effectiveZoom);
+        filterEffectBuilder->build(styleResolutionHost, filterStyle->filter(), effectiveZoom, &fillPaintForFilter, &strokePaintForFilter);
 
         SkiaImageFilterBuilder imageFilterBuilder;
         RefPtrWillBeRawPtr<FilterEffect> lastEffect = filterEffectBuilder->lastEffect();
         m_resolvedFilter = imageFilterBuilder.build(lastEffect.get(), ColorSpaceDeviceRGB);
     }
 
     return m_resolvedFilter.get();
 }
 
 SkDrawLooper* CanvasRenderingContext2DState::emptyDrawLooper() const
@@ skipping 209 matching lines @@
         paint->setLooper(0);
         paint->setImageFilter(shadowAndForegroundImageFilter());
         return paint;
     }
     paint->setLooper(shadowAndForegroundDrawLooper());
     paint->setImageFilter(0);
     return paint;
 }
 
 } // blink