Fix the WebRTC color bug.

media/base/simd/convert_yuv_to_rgb_c.cc

Index: media/base/simd/convert_yuv_to_rgb_c.cc
diff --git a/media/base/simd/convert_yuv_to_rgb_c.cc b/media/base/simd/convert_yuv_to_rgb_c.cc
index f04a89dbf9c7eb97825a37ff5ddf5c35164fca0f..e3a16f442bcb9936ab0a70a03e2bc7cd1d730c51 100644
--- a/media/base/simd/convert_yuv_to_rgb_c.cc
+++ b/media/base/simd/convert_yuv_to_rgb_c.cc
@@ -11,6 +11,24 @@ namespace media {
 #define paddsw(x, y) (((x) + (y)) < -32768 ? -32768 : \
     (((x) + (y)) > 32767 ? 32767 : ((x) + (y))))
 
+// On Android, pixel layout is RGBA
+// (see third_party/skia/include/core/SkColorPriv.h);
+// however, other Chrome platforms use BGRA
+// (see skia/config/SkUserConfig.h).
+// Ideally, android should not use the function here
+// due to performance issue(crbug/249980).

[scherkus (not reviewing), 2013/06/15 00:31:56]

nit: can you better format this comment?

for example ... try to use the full 80 character limit we have

links should also be full urls and clickable

e.g., http://crbug.com/249980

[hkuang1, 2013/06/15 00:54:01]

Done.

+#if defined(OS_ANDROID)
+#define SK_R32_SHIFT    0
+#define SK_G32_SHIFT    8
+#define SK_B32_SHIFT    16
+#define SK_A32_SHIFT    24
+#else
+#define SK_B32_SHIFT    0
+#define SK_G32_SHIFT    8
+#define SK_R32_SHIFT    16
+#define SK_A32_SHIFT    24
+#endif
+
 static inline void ConvertYUVToRGB32_C(uint8 y,
                                        uint8 u,
                                        uint8 v,
@@ -35,10 +53,10 @@ static inline void ConvertYUVToRGB32_C(uint8 y,
   r >>= 6;
   a >>= 6;
 
-  *reinterpret_cast<uint32*>(rgb_buf) = (packuswb(b)) |
-                                        (packuswb(g) << 8) |
-                                        (packuswb(r) << 16) |
-                                        (packuswb(a) << 24);
+  *reinterpret_cast<uint32*>(rgb_buf) = (packuswb(b) << SK_B32_SHIFT) |
+                                        (packuswb(g) << SK_G32_SHIFT) |
+                                        (packuswb(r) << SK_R32_SHIFT) |
+                                        (packuswb(a) << SK_A32_SHIFT);
 }
 
 static inline void ConvertYUVAToARGB_C(uint8 y,
@@ -66,7 +84,10 @@ static inline void ConvertYUVAToARGB_C(uint8 y,
   g = packuswb(g) * a >> 8;
   r = packuswb(r) * a >> 8;
 
-  *reinterpret_cast<uint32*>(rgb_buf) = b | (g << 8) | (r << 16) | (a << 24);
+  *reinterpret_cast<uint32*>(rgb_buf) = (b << SK_B32_SHIFT) |
+                                        (g << SK_G32_SHIFT) |
+                                        (r << SK_R32_SHIFT) |
+                                        (a << SK_A32_SHIFT);
 }
 
 void ConvertYUVToRGB32Row_C(const uint8* y_buf,