Clamp radii in FEMorphology::createImageFilter

Sk{Dilate,Erode}ImageFilter::Make take the radii as integers (int), so
make sure to convert the float FEMorphology stores avoiding overflow.

BUG=675164

Review-Url: https://codereview.chromium.org/2585233002
Cr-Commit-Position: refs/heads/master@{#439474}

third_party/WebKit/Source/platform/graphics/filters/FEMorphology.cpp

@@ -92,10 +92,8 @@ FloatRect FEMorphology::mapEffect(const FloatRect& rect) const {
 sk_sp<SkImageFilter> FEMorphology::createImageFilter() {
   sk_sp<SkImageFilter> input(
       SkiaImageFilterBuilder::build(inputEffect(0), operatingColorSpace()));
-  SkScalar radiusX =
-      SkFloatToScalar(getFilter()->applyHorizontalScale(m_radiusX));
-  SkScalar radiusY =
-      SkFloatToScalar(getFilter()->applyVerticalScale(m_radiusY));
+  int radiusX = clampTo<int>(getFilter()->applyHorizontalScale(m_radiusX));
+  int radiusY = clampTo<int>(getFilter()->applyVerticalScale(m_radiusY));
   SkImageFilter::CropRect rect = getCropRect();
   if (m_type == FEMORPHOLOGY_OPERATOR_DILATE)
     return SkDilateImageFilter::Make(radiusX, radiusY, std::move(input), &rect);