Bug 1642209 - Fix filtering of masked content r=emilio

Differential Revision: https://phabricator.services.mozilla.com/D186528

Author: longsonr

layout/svg/FilterInstance.cpp

@@ -64,7 +64,8 @@ static UniquePtr<UserSpaceMetrics> UserSpaceMetricsForFrame(nsIFrame* aFrame) {
 void FilterInstance::PaintFilteredFrame(
     nsIFrame* aFilteredFrame, Span<const StyleFilter> aFilterChain,
     gfxContext* aCtx, const SVGFilterPaintCallback& aPaintCallback,
-    const nsRegion* aDirtyArea, imgDrawingParams& aImgParams, float aOpacity) {
+    const nsRegion* aDirtyArea, imgDrawingParams& aImgParams, float aOpacity,
+    const gfxRect* aOverrideBBox) {
   UniquePtr<UserSpaceMetrics> metrics =
       UserSpaceMetricsForFrame(aFilteredFrame);
 
@@ -89,7 +90,7 @@ void FilterInstance::PaintFilteredFrame(
   FilterInstance instance(aFilteredFrame, aFilteredFrame->GetContent(),
                           *metrics, aFilterChain, /* InputIsTainted */ true,
                           aPaintCallback, scaleMatrixInDevUnits, aDirtyArea,
-                          nullptr, nullptr, nullptr);
+                          nullptr, nullptr, aOverrideBBox);
   if (instance.IsInitialized()) {
     // Pull scale vector out of aCtx's transform, put all scale factors, which
     // includes css and css-to-dev-px scale, into scaleMatrixInDevUnits.

layout/svg/FilterInstance.h

@@ -89,13 +89,11 @@ class FilterInstance {
    *   frame space (i.e. relative to its origin, the top-left corner of its
    *   border box).
    */
-  static void PaintFilteredFrame(nsIFrame* aFilteredFrame,
-                                 Span<const StyleFilter> aFilterChain,
-                                 gfxContext* aCtx,
-                                 const SVGFilterPaintCallback& aPaintCallback,
-                                 const nsRegion* aDirtyArea,
-                                 imgDrawingParams& aImgParams,
-                                 float aOpacity = 1.0f);
+  static void PaintFilteredFrame(
+      nsIFrame* aFilteredFrame, Span<const StyleFilter> aFilterChain,
+      gfxContext* aCtx, const SVGFilterPaintCallback& aPaintCallback,
+      const nsRegion* aDirtyArea, imgDrawingParams& aImgParams,
+      float aOpacity = 1.0f, const gfxRect* aOverrideBBox = nullptr);
 
   /**
    * Returns the post-filter area that could be dirtied when the given

layout/svg/SVGUtils.cpp

@@ -725,9 +725,14 @@ void SVGUtils::PaintFrameWithEffects(nsIFrame* aFrame, gfxContext& aContext,
                              : aTransform,
                          aImgParams);
     };
+    // If we're masking a userSpaceOnUse mask we may need to include the
+    // stroke too. Err on the side of caution and include it always.
+    gfxRect bbox = GetBBox(aFrame, SVGUtils::eUseFrameBoundsForOuterSVG |
+                                       SVGUtils::eBBoxIncludeFillGeometry |
+                                       SVGUtils::eBBoxIncludeStroke);
     FilterInstance::PaintFilteredFrame(
         aFrame, aFrame->StyleEffects()->mFilters.AsSpan(), target, callback,
-        nullptr, aImgParams);
+        nullptr, aImgParams, 1.0f, &bbox);
   } else {
     svgFrame->PaintSVG(*target, aTransform, aImgParams);
   }