Bug 1323962 - Should support CSS transform for pattern r=longsonr

The same as mask.

Differential Revision: https://phabricator.services.mozilla.com/D27882

--HG--
extra : moz-landing-system : lando

layout/reftests/svg/reftest.list

@@ -145,6 +145,7 @@ fuzzy-if(d2d||skiaContent,0-1,0-10000) == dynamic-filter-contents-01b.svg dynami
 == dynamic-mask-contents-01.svg pass.svg
 == dynamic-mask-pre-effects-bbox.html dynamic-mask-pre-effects-bbox-ref.html
 == test_bug1323962.html test_bug1323962-ref.html
+== test_bug1323962-2.html test_bug1323962-2-ref.html
 == dynamic-opacity-property-01.svg pass.svg
 == dynamic-pattern-01.svg pass.svg
 == dynamic-pattern-02.svg pass.svg

layout/reftests/svg/test_bug1323962-2-ref.html

@@ -0,0 +1,9 @@
+<svg width="200" height="200">
+  <defs>
+    <pattern id="Pattern" x="0" y="0" width=".25" height=".25">
+      <rect id="rec" x="0" y="0" width="30" height="30" fill="skyblue"/>
+    </pattern>
+  </defs>
+
+  <rect fill="url(#Pattern)" stroke="black" width="200" height="200"/>
+</svg>

layout/reftests/svg/test_bug1323962-2.html

@@ -0,0 +1,14 @@
+<style>
+#rec {
+  transform: scale(.6,.6);
+}
+</style>
+<svg width="200" height="200">
+  <defs>
+    <pattern id="Pattern" x="0" y="0" width=".25" height=".25">
+      <rect id="rec" x="0" y="0" width="50" height="50" fill="skyblue"/>
+    </pattern>
+  </defs>
+
+  <rect fill="url(#Pattern)" stroke="black" width="200" height="200"/>
+</svg>

layout/svg/nsSVGPatternFrame.cpp

@@ -355,15 +355,13 @@ already_AddRefed<SourceSurface> nsSVGPatternFrame::PaintPattern(
         NS_FRAME_DRAWING_AS_PAINTSERVER)) {
     AutoSetRestorePaintServerState paintServer(patternWithChildren);
     for (nsIFrame *kid = firstKid; kid; kid = kid->GetNextSibling()) {
+      gfxMatrix tm = *(patternWithChildren->mCTM);
+
       // The CTM of each frame referencing us can be different
       nsSVGDisplayableFrame *SVGFrame = do_QueryFrame(kid);
       if (SVGFrame) {
         SVGFrame->NotifySVGChanged(nsSVGDisplayableFrame::TRANSFORM_CHANGED);
-      }
-      gfxMatrix tm = *(patternWithChildren->mCTM);
-      if (kid->GetContent()->IsSVGElement()) {
-        tm = static_cast<SVGElement *>(kid->GetContent())
-                 ->PrependLocalTransformsTo(tm, eUserSpaceToParent);
+        tm = nsSVGUtils::GetTransformMatrixInUserSpace(kid, patternWithChildren) * tm;
       }
 
       nsSVGUtils::PaintFrameWithEffects(kid, *ctx, tm, aImgParams);