[code-cache] Keep code alive for a little longer

Code ageing too early can have a bad impact on performance. Let's
evaluate keeping code alive a little longer. Later we can look at more
elaborate heuristics.

Change-Id: Ib220c4dcd24165d6b6e5020cb1829c669ed3e736
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3686416
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80920}

src/objects/code.h

@@ -971,7 +971,7 @@ class BytecodeArray
     kFirstBytecodeAge = kNoAgeBytecodeAge,
     kLastBytecodeAge = kAfterLastBytecodeAge - 1,
     kBytecodeAgeCount = kAfterLastBytecodeAge - kFirstBytecodeAge - 1,
-    kIsOldBytecodeAge = kSexagenarianBytecodeAge
+    kIsOldBytecodeAge = kOctogenarianBytecodeAge
   };
 
   static constexpr int SizeFor(int length) {