Bug 939942 - Reflow when bounds changes due to stroke creation/removal. r=jwatt

layout/reftests/svg/dynamic-stroke-01.svg

@@ -0,0 +1,21 @@
+<!--
+    Any copyright is dedicated to the Public Domain.
+    http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<svg xmlns="http://www.w3.org/2000/svg" class="reftest-wait">
+
+  <title>Test for changing stroke from none to a solid color value</title>
+
+  <!-- From https://bugzilla.mozilla.org/show_bug.cgi?id=939942 -->
+
+  <rect width="100%" height="100%" fill="red"/>
+
+  <rect id="r" width="100%" height="50%" y="25%" stroke="none" stroke-width="75%" fill="lime"/>
+
+  <script>
+    window.addEventListener("MozReftestInvalidate", function() {
+      document.getElementById("r").style.stroke = "lime";
+      document.documentElement.removeAttribute("class");
+    }, false);
+  </script>
+</svg>

layout/reftests/svg/dynamic-stroke-opacity-01.svg

@@ -0,0 +1,21 @@
+<!--
+    Any copyright is dedicated to the Public Domain.
+    http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<svg xmlns="http://www.w3.org/2000/svg" class="reftest-wait">
+
+  <title>Test for changing stroke-opacity from 0 to non-zero</title>
+
+  <!-- From https://bugzilla.mozilla.org/show_bug.cgi?id=939942 -->
+
+  <rect width="100%" height="100%" fill="red"/>
+
+  <rect id="r" width="100%" height="50%" y="25%" stroke-opacity="0" stroke="lime" stroke-width="75%" fill="lime"/>
+
+  <script>
+    window.addEventListener("MozReftestInvalidate", function() {
+      document.getElementById("r").style.strokeOpacity = "1";
+      document.documentElement.removeAttribute("class");
+    }, false);
+  </script>
+</svg>

layout/reftests/svg/dynamic-stroke-width-01.svg

@@ -0,0 +1,21 @@
+<!--
+    Any copyright is dedicated to the Public Domain.
+    http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<svg xmlns="http://www.w3.org/2000/svg" class="reftest-wait">
+
+  <title>Test for changing stroke-width from zero to non-zero</title>
+
+  <!-- From https://bugzilla.mozilla.org/show_bug.cgi?id=939942 -->
+
+  <rect width="100%" height="100%" fill="red"/>
+
+  <rect id="r" width="100%" height="50%" y="25%" stroke="lime" stroke-width="0" fill="lime"/>
+
+  <script>
+    window.addEventListener("MozReftestInvalidate", function() {
+      document.getElementById("r").style.strokeWidth = "75%";
+      document.documentElement.removeAttribute("class");
+    }, false);
+  </script>
+</svg>

layout/reftests/svg/reftest.list

@@ -102,6 +102,9 @@ skip-if(B2G) == dynamic-pattern-contents-02.svg pass.svg
 == dynamic-reflow-01.svg dynamic-reflow-01-ref.svg
 == dynamic-small-object-scaled-up-01.svg pass.svg
 == dynamic-small-object-scaled-up-02.svg pass.svg
+== dynamic-stroke-01.svg pass.svg
+== dynamic-stroke-opacity-01.svg pass.svg
+== dynamic-stroke-width-01.svg pass.svg
 == dynamic-switch-01.svg pass.svg
 == dynamic-text-01.svg dynamic-text-01-ref.svg
 fuzzy-if(d2d&&layersGPUAccelerated,2,12739) == dynamic-text-02.svg dynamic-text-02-ref.svg # bug 776038 for Win7

layout/style/nsStyleStruct.cpp

@@ -944,8 +944,21 @@ nsChangeHint nsStyleSVG::CalcDifference(const nsStyleSVG& aOther) const
   }
 
   if (mFill != aOther.mFill ||
-      mStroke != aOther.mStroke) {
+      mStroke != aOther.mStroke ||
+      mFillOpacity != aOther.mFillOpacity ||
+      mStrokeOpacity != aOther.mStrokeOpacity) {
     NS_UpdateHint(hint, nsChangeHint_RepaintFrame);
+    if (HasStroke() != aOther.HasStroke() ||
+        (!HasStroke() && HasFill() != aOther.HasFill())) {
+      // Frame bounds and overflow rects depend on whether we "have" fill or
+      // stroke. Whether we have stroke or not just changed, or else we have no
+      // stroke (in which case whether we have fill or not is significant to frame
+      // bounds) and whether we have fill or not just changed. In either case we
+      // need to reflow so the frame rect is updated.
+      // XXXperf this is a waste on non nsSVGPathGeometryFrames.
+      NS_UpdateHint(hint, nsChangeHint_NeedReflow);
+      NS_UpdateHint(hint, nsChangeHint_NeedDirtyReflow); // XXX remove me: bug 876085
+    }
     if (PaintURIChanged(mFill, aOther.mFill) ||
         PaintURIChanged(mStroke, aOther.mStroke)) {
       NS_UpdateHint(hint, nsChangeHint_UpdateEffects);
@@ -975,8 +988,6 @@ nsChangeHint nsStyleSVG::CalcDifference(const nsStyleSVG& aOther) const
   }
 
   if ( mStrokeDashoffset      != aOther.mStrokeDashoffset      ||
-       mFillOpacity           != aOther.mFillOpacity           ||
-       mStrokeOpacity         != aOther.mStrokeOpacity         ||
        mClipRule              != aOther.mClipRule              ||
        mColorInterpolation    != aOther.mColorInterpolation    ||
        mColorInterpolationFilters != aOther.mColorInterpolationFilters ||

layout/style/nsStyleStruct.h

@@ -2387,6 +2387,22 @@ struct nsStyleSVG {
   bool HasMarker() const {
     return mMarkerStart || mMarkerMid || mMarkerEnd;
   }
+
+  /**
+   * Returns true if the stroke is not "none" and the stroke-opacity is greater
+   * than zero. This ignores stroke-widths as that depends on the context.
+   */
+  bool HasStroke() const {
+    return mStroke.mType != eStyleSVGPaintType_None && mStrokeOpacity > 0;
+  }
+
+  /**
+   * Returns true if the fill is not "none" and the fill-opacity is greater
+   * than zero.
+   */
+  bool HasFill() const {
+    return mFill.mType != eStyleSVGPaintType_None && mFillOpacity > 0;
+  }
 };
 
 struct nsStyleFilter {

layout/svg/nsSVGTextFrame2.cpp

@@ -5052,11 +5052,10 @@ nsSVGTextFrame2::ShouldRenderAsPath(nsRenderingContext* aContext,
   }
 
   // Text has a stroke.
-  if (!(style->mStroke.mType == eStyleSVGPaintType_None ||
-        style->mStrokeOpacity == 0 ||
-        SVGContentUtils::CoordToFloat(PresContext(),
-                                      static_cast<nsSVGElement*>(mContent),
-                                      style->mStrokeWidth) == 0)) {
+  if (style->HasStroke() &&
+      SVGContentUtils::CoordToFloat(PresContext(),
+                                    static_cast<nsSVGElement*>(mContent),
+                                    style->mStrokeWidth) > 0) {
     return true;
   }
 

layout/svg/nsSVGUtils.cpp

@@ -1245,9 +1245,7 @@ nsSVGUtils::CanOptimizeOpacity(nsIFrame *aFrame)
   if (style->HasMarker()) {
     return false;
   }
-  if (style->mFill.mType == eStyleSVGPaintType_None ||
-      style->mFillOpacity <= 0 ||
-      !HasStroke(aFrame)) {
+  if (!style->HasFill() || !HasStroke(aFrame)) {
     return true;
   }
   return false;
@@ -1559,9 +1557,7 @@ bool
 nsSVGUtils::HasStroke(nsIFrame* aFrame, gfxTextContextPaint *aContextPaint)
 {
   const nsStyleSVG *style = aFrame->StyleSVG();
-  return style->mStroke.mType != eStyleSVGPaintType_None &&
-         style->mStrokeOpacity > 0 &&
-         GetStrokeWidth(aFrame, aContextPaint) > 0;
+  return style->HasStroke() && GetStrokeWidth(aFrame, aContextPaint) > 0;
 }
 
 float