Circling back on this.
We're very close to fulfilling this dream.
A quick grep of the source this morning shows only a few ENABLE_ macros left:
grep -r ENABLE\( * -h | grep -v "//" | sort | uniq -c | sort -r -n
(small amount of editing)
3 #if ENABLE(DEFAULT_RENDER_THEME)
3 #if !ENABLE(RUBBER_BANDING)
3 #if ENABLE(THREADING_GENERIC)
4 #if ENABLE(COMPARE_AND_SWAP)
4 #if !ENABLE(INPUT_MULTIPLE_FIELDS_UI)
4 #if ENABLE(PARTITION_ALLOC)
4 #if ENABLE(STREAM)
4 #if ENABLE(VERBOSE_STACK_STATS)
6 #if ENABLE(TCMALLOC_HARDENING)
6 #if ENABLE(TOUCH_ICON_LOADING)
8 #if ENABLE(ACCELERATED_OVERFLOW_SCROLLING)
8 #if ENABLE(NAVIGATOR_CONTENT_UTILS)
9 #if ENABLE(8BIT_TEXTRUN)
11 #if ENABLE(ORIENTATION_EVENTS)
12 #if ENABLE(ENCRYPTED_MEDIA_V2)
12 #if ENABLE(USERSELECT_ALL)
13 #if ENABLE(MEDIA_CAPTURE)
16 #if ENABLE(NOTIFICATIONS)
18 #if ENABLE(OPENTYPE_VERTICAL)
18 #if ENABLE(PAN_SCROLLING)
21 #if ENABLE(CALENDAR_PICKER)
21 #if ENABLE(LEGACY_NOTIFICATIONS)
21 #if ENABLE(WTF_MALLOC_VALIDATION)
24 #if ENABLE(NOTIFICATIONS) || ENABLE(LEGACY_NOTIFICATIONS)
25 #if ENABLE(RUBBER_BANDING)
28 #if ENABLE(SVG)
42 #if ENABLE(WEBVTT_REGIONS)
52 #if ENABLE(CSS3_TEXT)
71 #if ENABLE(INPUT_SPEECH)
79 #if ENABLE(INPUT_MULTIPLE_FIELDS_UI)
100 #if ENABLE(SVG_FONTS)
120 #if ENABLE(WEB_AUDIO)