Harmonize FilterEffect::mapRect and mapPaintRect

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

Index: third_party/WebKit/Source/platform/graphics/filters/FELighting.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/filters/FELighting.cpp b/third_party/WebKit/Source/platform/graphics/filters/FELighting.cpp
index 70d588f4ded39b32140c35e569a66dfb0939c411..2c1c226694039ee3bde077071a58bd73af1d903e 100644
--- a/third_party/WebKit/Source/platform/graphics/filters/FELighting.cpp
+++ b/third_party/WebKit/Source/platform/graphics/filters/FELighting.cpp
@@ -50,14 +50,6 @@ FELighting::FELighting(Filter* filter, LightingType lightingType, const Color& l
 {
 }
 
-FloatRect FELighting::mapPaintRect(const FloatRect& rect, bool) const
-{
-    FloatRect result = rect;
-    // The areas affected need to be a pixel bigger to accommodate the Sobel kernel.
-    result.inflate(1);

[Stephen White, 2016/09/20 15:36:19]

pdr@ attempted to remove this before. I don't think we can remove it, since it
seems like invalidating the interior of a rect should invalidate the pixels
bordering that rect, due to the Sobel kernel. Either I'm wrong, or our testing
is insufficient here (probably needs something where the inner border of the
invalidation region contains some interesting pixels (ie., not solid colour)).

[fs, 2016/09/20 19:14:15]

And he didn't leave a trail of regression tests after (trying) that? =)

Not particularly easy to dream up a reasonable test for this, but added
something. I don't carry high hopes that one will ever catch anything though
(given how the lighting filters will essentially be returning the full region.)
It's there for discussion and tweaks (and "somethingness") though.

-    return result;
-}
-
 sk_sp<SkImageFilter> FELighting::createImageFilter()
 {
     if (!m_lightSource)