range-diff should suppress context-only changes?

> Range-diff vs v3:
> [...]
>   7:  42633b8d03 !  7:  5e8004c728 strmap: add more utility functions
>      @@ strmap.h: void *strmap_get(struct strmap *map, const char *str);
>       + * iterate through @map using @iter, @var is a pointer to a type strmap_entry
>       + */
>       +#define strmap_for_each_entry(mystrmap, iter, var)	\
>      -+	for (var = hashmap_iter_first_entry_offset(&(mystrmap)->map, iter, 0); \
>      -+		var; \
>      -+		var = hashmap_iter_next_entry_offset(iter, 0))
>      ++	hashmap_for_each_entry(&(mystrmap)->map, iter, var, ent)
>       +
>        #endif /* STRMAP_H */
>   8:  ea942eb803 =  8:  fd96e9fc8d strmap: enable faster clearing and reusing of strmaps
>   9:  c1d2172171 !  9:  f499934f54 strmap: add functions facilitating use as a string->int map
> [...]
>       @@ strmap.h: static inline int strmap_empty(struct strmap *map)
>      - 		var; \
>      - 		var = hashmap_iter_next_entry_offset(iter, 0))
>      + #define strmap_for_each_entry(mystrmap, iter, var)	\
>      + 	hashmap_for_each_entry(&(mystrmap)->map, iter, var, ent)
>        
>       +
>       +/*
>      @@ strmap.h: static inline int strmap_empty(struct strmap *map)