Revert of experiment: float color components

src/core/SkColorShader.h

Index: src/core/SkColorShader.h
diff --git a/src/core/SkColorShader.h b/src/core/SkColorShader.h
index 1c07a3c124b2cb0783cf8e40d7aca63b68cab2ee..25a1d6c8d072144d5b1d117f359bd2ac9e43192c 100644
--- a/src/core/SkColorShader.h
+++ b/src/core/SkColorShader.h
@@ -36,10 +36,8 @@
         uint32_t getFlags() const override;
         void shadeSpan(int x, int y, SkPMColor span[], int count) override;
         void shadeSpanAlpha(int x, int y, uint8_t alpha[], int count) override;
-        void shadeSpan4f(int x, int y, SkPM4f[], int count) override;
 
     private:
-        SkPM4f      fPM4f;
         SkPMColor   fPMColor;
         uint32_t    fFlags;