Fix Red/Blue decoding problem in WebP.

src/images/SkImageDecoder_libwebp.cpp

 /*
  * Copyright 2010, The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
@@ skipping 155 matching lines @@
 static bool return_false(const SkBitmap& bm, const char msg[]) {
     SkDEBUGF(("libwebp error %s [%d %d]", msg, bm.width(), bm.height()));
     return false; // must always return false
 }
 
 static WEBP_CSP_MODE webp_decode_mode(const SkBitmap* decodedBitmap, bool premultiply) {
     WEBP_CSP_MODE mode = MODE_LAST;
     SkBitmap::Config config = decodedBitmap->config();
 
     if (config == SkBitmap::kARGB_8888_Config) {
-        mode = premultiply ? MODE_rgbA : MODE_RGBA;
+        #if SK_PMCOLOR_BYTE_ORDER(B,G,R,A)
+            mode = premultiply ? MODE_bgrA : MODE_BGRA;
+        #elif SK_PMCOLOR_BYTE_ORDER(R,G,B,A)
+            mode = premultiply ? MODE_rgbA : MODE_RGBA;
+        #else
+            #error "Skia uses BGRA or RGBA byte order"
+        #endif
     } else if (config == SkBitmap::kARGB_4444_Config) {
         mode = premultiply ? MODE_rgbA_4444 : MODE_RGBA_4444;
     } else if (config == SkBitmap::kRGB_565_Config) {
         mode = MODE_RGB_565;
     }
     SkASSERT(MODE_LAST != mode);
     return mode;
 }
 
 // Incremental WebP image decoding. Reads input buffer of 64K size iteratively
@@ skipping 403 matching lines @@
     return SkImageDecoder::kUnknown_Format;
 }
 
 static SkImageEncoder* sk_libwebp_efactory(SkImageEncoder::Type t) {
       return (SkImageEncoder::kWEBP_Type == t) ? SkNEW(SkWEBPImageEncoder) : NULL;
 }
 
 static SkImageDecoder_DecodeReg gDReg(sk_libwebp_dfactory);
 static SkImageDecoder_FormatReg gFormatReg(get_format_webp);
 static SkImageEncoder_EncodeReg gEReg(sk_libwebp_efactory);