Scanline decoding for bmp

src/codec/SkBmpRLECodec.cpp

Index: src/codec/SkBmpRLECodec.cpp
diff --git a/src/codec/SkBmpRLECodec.cpp b/src/codec/SkBmpRLECodec.cpp
index 14a5b01c1f374d520856058aeef61ef9978324d3..646e20c217cfed21cddfd49fdcc0ea6e9026ef96 100644
--- a/src/codec/SkBmpRLECodec.cpp
+++ b/src/codec/SkBmpRLECodec.cpp
@@ -456,3 +456,24 @@ SkCodec::Result SkBmpRLECodec::decode(const SkImageInfo& dstInfo,
         }
     }
 }
+
+SkCodec::Result SkBmpRLECodec::onStart(const SkImageInfo& dstInfo,
+        const SkCodec::Options& options, SkPMColor inputColorPtr[], int* inputColorCount) {
+    // Create the color table if necessary and prepare the stream for decode
+    // Note that if it is non-NULL, inputColorCount will be modified
+    if (!this->createColorTable(inputColorCount)) {
+        SkCodecPrintf("Error: could not create color table.\n");
+        return SkCodec::kInvalidInput;
+    }
+
+    // Copy the color table to the client if necessary
+    copy_color_table(dstInfo, this->fColorTable, inputColorPtr, inputColorCount);
+
+    // Initialize a buffer for encoded RLE data
+    if (!this->initializeStreamBuffer()) {
+        SkCodecPrintf("Error: cannot initialize swizzler.\n");
+        return SkCodec::kInvalidConversion;
+    }
+
+    return SkCodec::kSuccess;
+}