Improved include paths for projects using SDL on Android

Isaac Burns

I wanted to suggest a few changes I've found that help the Android build.  By adding LOCAL_EXPORT_C_INCLUDES to the Android.mk file, anything that references the SDL Android project will inherit the include paths.
Fixed bugs 1914, 1915 - sizeof(const char**) is suspicious

Nitz

In function:
static void add_music_decoder(const char *decoder)
{
        void *ptr = SDL_realloc(music_decoders, (num_decoders + 1) * sizeof (const char **));
        if (ptr == NULL) {
                return;  /* oh well, go on without it. */
        }
        music_decoders = (const char **) ptr;
        music_decoders[num_decoders++] = decoder;
}

Passing argument sizeof(char const **) to function SDL_realloc is suspicious.

Logically it should be sizeof(char const *) instead of sizeof (char const **)

In this particular case sizeof(char const **) happens to be equal to sizeof(char const *), but this is not a portable assumption.
It reduces the understanding of the user.

So Patch should be,
void *ptr=SDL_realloc(music_decoders,(num_decoders+1) * sizeof(const char *));