6 canvas->
clear(0x8055aaff);
REG_FIDDLE(Canvas_readPixels_3, 256, 256, true, 0)
void SK_SPI SkDebugf(const char format[],...) SK_PRINTF_LIKE(1
static void draw(SkCanvas *canvas, SkRect &target, int x, int y)
void clear(SkColor color)
bool readPixels(const SkImageInfo &dstInfo, void *dstPixels, size_t dstRowBytes, int srcX, int srcY)
static SkImageInfo MakeN32Premul(int width, int height)