[sparkplug] Enable short builtin calls by default (#3)

... when they are enabled via the GN flag.

Known issues are already fixed in a separate CL:
  https://chromium-review.googlesource.com/c/v8/v8/+/2786855

Sheriffs: This CL adds ~1.2-1.4Mb of memory overhead per Isolate on
certain configurations and that's expected. This is a temporary fix
until the full solution is implemented.
See the design doc linked to the issue for details.

Bug: v8:11527
Change-Id: Ia472352926494f59481e8ddc54e15c75f5730730
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2786840
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73691}

src/flags/flag-definitions.h

@@ -1546,7 +1546,7 @@ DEFINE_BOOL(experimental_flush_embedded_blob_icache, false,
 #define V8_SHORT_BUILTIN_CALLS_BOOL false
 #endif
 
-DEFINE_BOOL(short_builtin_calls, false,
+DEFINE_BOOL(short_builtin_calls, V8_SHORT_BUILTIN_CALLS_BOOL,
             "Put embedded builtins code into the code range for shorter "
             "builtin calls/jumps if system has >=4GB memory")