Revert of Enabling ico decoding with use of png and bmp decoders

src/codec/SkCodec_libico.h

-/*
- * Copyright 2015 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "SkCodec.h"
-#include "SkImageInfo.h"
-#include "SkStream.h"
-#include "SkTypes.h"
-
-/*
- * This class implements the decoding for bmp images
- */
-class SkIcoCodec : public SkCodec {
-public:
-
-    /*
-     * Checks the start of the stream to see if the image is a Ico or Cur
-     */
-    static bool IsIco(SkStream*);
-
-    /*
-     * Assumes IsIco was called and returned true
-     * Creates an Ico decoder
-     * Reads enough of the stream to determine the image format
-     */
-    static SkCodec* NewFromStream(SkStream*);
-
-protected:
-
-    /*
-     * Chooses the best dimensions given the desired scale
-     */
-    SkISize onGetScaledDimensions(float desiredScale) const SK_OVERRIDE;
-
-    /*
-     * Initiates the Ico decode
-     */
-    Result onGetPixels(const SkImageInfo& dstInfo, void* dst,
-                       size_t dstRowBytes, const Options&, SkPMColor*, int*)
-                       SK_OVERRIDE;
-
-    SkEncodedFormat onGetEncodedFormat() const SK_OVERRIDE {
-        return kICO_SkEncodedFormat;
-    }
-
-private:
-
-    /*
-     * Constructor called by NewFromStream
-     * @param embeddedCodecs codecs for the embedded images, takes ownership
-     */
-    SkIcoCodec(const SkImageInfo& srcInfo,
-               SkTArray<SkAutoTDelete<SkCodec>, true>* embeddedCodecs);
-
-    SkAutoTDelete<SkTArray<SkAutoTDelete<SkCodec>, true>>
-            fEmbeddedCodecs; // owned
-
-    typedef SkCodec INHERITED;
-};