Bug 1127507 - Get transforms on the children of SVG <mask> working. r=dholbert

--HG--
extra : rebase_source : 1569a6e4e5f72f71fb47486cdc99f9c64d15b689

layout/reftests/svg/mask-transformed-child-01-ref.svg

@@ -0,0 +1,8 @@
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<svg xmlns="http://www.w3.org/2000/svg">
+  <rect x="50" y="75" width="100" height="50" fill="blue"/>
+</svg>
+

layout/reftests/svg/mask-transformed-child-01.svg

@@ -0,0 +1,11 @@
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<svg xmlns="http://www.w3.org/2000/svg">
+  <mask id="mask" maskUnits="objectBoundingBox" maskContentUnits="objectBoundingBox">
+    <rect x="0.25" y="0" width="0.5" height="1" fill="white" transform="rotate(90,0.5,0.5)"/>
+  </mask>
+  <rect x="50" y="50" width="100" height="100" fill="blue" mask="url(#mask)"/>
+</svg>
+

layout/reftests/svg/reftest.list

@@ -209,6 +209,7 @@ pref(svg.marker-improvements.enabled,true) == marker-orientation-02.svg marker-o
 == mask-containing-masked-content-01.svg pass.svg
 == mask-transformed-01.svg mask-transformed-01-ref.svg
 == mask-transformed-02.svg pass.svg
+== mask-transformed-child-01.svg mask-transformed-child-01-ref.svg
 pref(layout.css.masking.enabled,true) fuzzy-if(d2d,1,6400) == mask-type-01.svg mask-type-01-ref.svg
 pref(layout.css.masking.enabled,true) fuzzy-if(d2d,1,6400) == mask-type-02.svg mask-type-01-ref.svg
 pref(layout.css.masking.enabled,true) fuzzy-if(d2d,1,6400) == mask-type-03.svg mask-type-01-ref.svg

layout/svg/nsSVGMaskFrame.cpp

@@ -277,7 +277,7 @@ nsSVGMaskFrame::GetMaskForMaskedFrame(gfxContext* aContext,
       m = static_cast<nsSVGElement*>(kid->GetContent())->
             PrependLocalTransformsTo(m);
     }
-    nsSVGUtils::PaintFrameWithEffects(kid, *tmpCtx, mMatrixForChildren);
+    nsSVGUtils::PaintFrameWithEffects(kid, *tmpCtx, m);
   }
 
   RefPtr<SourceSurface> maskSnapshot = maskDT->Snapshot();