Create special surfaces according to original device (not always in N32)

src/core/SkImageFilter.cpp

Index: src/core/SkImageFilter.cpp
diff --git a/src/core/SkImageFilter.cpp b/src/core/SkImageFilter.cpp
index be48ca17ba101b231b7708af7ef7804bcef583f5..9373dc1a1d3cc5f28badce7355f32ef9cea59990 100644
--- a/src/core/SkImageFilter.cpp
+++ b/src/core/SkImageFilter.cpp
@@ -348,9 +348,9 @@ bool SkImageFilter::applyCropRect(const Context& ctx, const SkIRect& srcBounds,
 // around it.
 static sk_sp<SkSpecialImage> pad_image(SkSpecialImage* src,
                                        int newWidth, int newHeight, int offX, int offY) {

[robertphillips, 2016/09/23 14:11:28]

Although SpecialImages are inextricably tied to ImageFilters it still seems odd
for makeSurface to be so reliant on a struct from SkImageFilter (i.e.,
OutputProperties).

-
-    SkImageInfo info = SkImageInfo::MakeN32Premul(newWidth, newHeight);
-    sk_sp<SkSpecialSurface> surf(src->makeSurface(info));
+    // We explicitly want to operate in the source's color space here
+    SkImageFilter::OutputProperties outProps(src->getColorSpace());
+    sk_sp<SkSpecialSurface> surf(src->makeSurface(outProps, SkISize::Make(newWidth, newHeight)));
     if (!surf) {
         return nullptr;
     }