Separate out mux and demux code and libraries:

- Separate out mux.h and demux.h
- muxtypes.h: new header for data types common to mux/demux
- Move some misc read/write utilities to utils/utils.h
- Remove some duplicate methods.
- Separate out mux/demux libraries

Change-Id: If9b9569b10d55d922ad9317ef51710544315d6de

src/webp/format_constants.h

@@ -70,14 +70,18 @@ typedef enum {
 #define FRGM_CHUNK_SIZE    6     // Size of a FRGM chunk.
 #define VP8X_CHUNK_SIZE    10    // Size of a VP8X chunk.
 
-// VP8X Feature Flags. These should be the same as the corresponding values in
-// the 'WebPFeatureFlags' enum defined in mux.h.
-#define FRAGMENTS_FLAG_BIT 0x01
-#define ANIMATION_FLAG_BIT 0x02
-#define XMP_FLAG_BIT       0x04
-#define EXIF_FLAG_BIT      0x08
-#define ALPHA_FLAG_BIT     0x10
-#define ICC_FLAG_BIT       0x20
+// VP8X Feature Flags.
+#if !(defined(__cplusplus) || defined(c_plusplus))
+typedef enum WebPFeatureFlags WebPFeatureFlags;
+#endif
+enum WebPFeatureFlags {
+  FRAGMENTS_FLAG  = 0x00000001,
+  ANIMATION_FLAG  = 0x00000002,
+  XMP_FLAG        = 0x00000004,
+  EXIF_FLAG       = 0x00000008,
+  ALPHA_FLAG      = 0x00000010,
+  ICCP_FLAG       = 0x00000020
+};
 
 #define MAX_CANVAS_SIZE     (1 << 24)    // 24-bit max for VP8X width/height.
 #define MAX_IMAGE_AREA      (1ULL << 32) // 32-bit max for width x height.