Support more swizzles to 565 in SkCodec

src/codec/SkBmpMaskCodec.cpp

 /*
  * 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 "SkBmpMaskCodec.h"
 #include "SkCodecPriv.h"
 #include "SkColorPriv.h"
 
 /*
- * Checks if the conversion between the input image and the requested output
- * image has been implemented
- */
-static bool conversion_possible(const SkImageInfo& dst,
-                                const SkImageInfo& src) {
-    // Ensure that the profile type is unchanged
-    if (dst.profileType() != src.profileType()) {
-        return false;
-    }
-
-    // Ensure the alpha type is valid
-    if (!valid_alpha(dst.alphaType(), src.alphaType())) {
-        return false;
-    }
-
-    // Check for supported color types
-    switch (dst.colorType()) {
-        // Allow output to kN32
-        case kN32_SkColorType:
-            return true;
-        default:
-            return false;
-    }
-}
-
-
-/*
  * Creates an instance of the decoder
  */
 SkBmpMaskCodec::SkBmpMaskCodec(const SkImageInfo& info, SkStream* stream,
                                uint16_t bitsPerPixel, SkMasks* masks,
                                SkBmpCodec::RowOrder rowOrder)
     : INHERITED(info, stream, bitsPerPixel, rowOrder)
     , fMasks(masks)
     , fMaskSwizzler(NULL)
     , fSrcBuffer(NULL)
 {}
@@ skipping 78 matching lines @@
 
         // Decode the row in destination format
         int row = SkBmpCodec::kBottomUp_RowOrder == this->rowOrder() ? height - 1 - y : y;
         void* dstRow = SkTAddOffset<void>(dst, row * dstRowBytes);
         fMaskSwizzler->swizzle(dstRow, srcRow);
     }
 
     // Finished decoding the entire image
     return kSuccess;
 }