[ptr-compr] Disable double fields unboxing

Double field unboxing optimization is incompatible with pointer compression so
we land this CL before enabling pointer compression in order to separate memory
and performance regressions caused by disabled double field unboxing from
pointer compression change.

Bug: v8:9799
Change-Id: Ic8118356496a3f351344215b409f9722de6c9355
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1835546
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64089}

src/common/globals.h

@@ -77,7 +77,7 @@ constexpr int kStackSpaceRequiredForCompilation = 40;
 
 // Determine whether double field unboxing feature is enabled.
 #if V8_TARGET_ARCH_64_BIT && !defined(V8_COMPRESS_POINTERS)
-#define V8_DOUBLE_FIELDS_UNBOXING true
+#define V8_DOUBLE_FIELDS_UNBOXING false
 #else
 #define V8_DOUBLE_FIELDS_UNBOXING false
 #endif