Fill incomplete images in SkCodec parent class

src/codec/SkSampler.h

Index: src/codec/SkSampler.h
diff --git a/src/codec/SkSampler.h b/src/codec/SkSampler.h
index d7b4c98f235ad1ccb15afa7ff77997aa6d621372..1e7659e9e8623aade960dc388baec4ce09ebb51e 100644
--- a/src/codec/SkSampler.h
+++ b/src/codec/SkSampler.h
@@ -19,8 +19,49 @@ public:
         return this->onSetSampleX(sampleX);
     }
 
+    /**
+     * Fill the remainder of the destination with a single color
+     *
+     * @param dst
+     * The destination row to fill from.
+     *
+     * @param colorType
+     * The color type of the rows to fill.
+     *
+     * @param numRows
+     * The number of rows that we need to fill.
+     *
+     * @param rowBytes
+     * Stride in bytes of the destination.
+     *
+     * @param colorOrIndex
+     * If colorType is kN32, colorOrIndex is treated as a 32-bit color.
+     * If colorType is k565, colorOrIndex is treated as a 16-bit color.
+     * If colorType is kGray, colorOrIndex is treated as an 8-bit color.
+     * If colorType is kIndex, colorOrIndex is treated as an 8-bit index.
+     * Other SkColorTypes are not supported.
+     *
+     * @param zeroInit
+     * Indicates whether memory is already zero initialized.
+     *
+     */
+    void fill(void* dst, SkColorType colorType, int numRows, size_t rowBytes, uint32_t colorOrIndex,
+            SkCodec::ZeroInitialized zeroInit);
+
     virtual ~SkSampler() {}
 private:
+    /**
+     * Get the the scaled width of the image.
+     *
+     * SkSampler needs the scaled width to fill uninitialized memory in
+     * incomplete images.
+     */
+    int getScaledWidth() {
+        return this->onGetScaledWidth();
+    }
+
+    virtual int onGetScaledWidth() = 0;
+
     virtual int onSetSampleX(int) = 0;
 };