Bug 1248223 - verify that stroke widths are finite for Skia. r=jmuizelaar

gfx/2d/HelpersSkia.h

@@ -142,7 +142,8 @@ StrokeOptionsToPaint(SkPaint& aPaint, const StrokeOptions &aOptions)
 {
   // Skia renders 0 width strokes with a width of 1 (and in black),
   // so we should just skip the draw call entirely.
-  if (!aOptions.mLineWidth) {
+  // Skia does not handle non-finite line widths.
+  if (!aOptions.mLineWidth || !IsFinite(aOptions.mLineWidth)) {
     return false;
   }
   aPaint.setStrokeWidth(SkFloatToScalar(aOptions.mLineWidth));

gfx/2d/PathSkia.cpp

@@ -190,7 +190,9 @@ PathSkia::StrokeContainsPoint(const StrokeOptions &aStrokeOptions,
   }
 
   SkPaint paint;
-  StrokeOptionsToPaint(paint, aStrokeOptions);
+  if (!StrokeOptionsToPaint(paint, aStrokeOptions)) {
+    return false;
+  }
 
   SkPath strokePath;
   paint.getFillPath(mPath, &strokePath);
@@ -218,8 +220,10 @@ PathSkia::GetStrokedBounds(const StrokeOptions &aStrokeOptions,
   }
 
   SkPaint paint;
-  StrokeOptionsToPaint(paint, aStrokeOptions);
-  
+  if (!StrokeOptionsToPaint(paint, aStrokeOptions)) {
+    return Rect();
+  }
+
   SkPath result;
   paint.getFillPath(mPath, &result);