[turbofan] Rename --context-specialization to --function-context-specialization.

test/cctest/test-serialize.cc

Index: test/cctest/test-serialize.cc
diff --git a/test/cctest/test-serialize.cc b/test/cctest/test-serialize.cc
index bf36081201f57e4a9938ab9d10e7a49812d02299..a37d6a0f19a7bca0429f6a94283bd712a038d1af 100644
--- a/test/cctest/test-serialize.cc
+++ b/test/cctest/test-serialize.cc
@@ -1599,7 +1599,7 @@ TEST(SerializeInternalReference) {
   return;
 #endif
   // Disable experimental natives that are loaded after deserialization.
-  FLAG_context_specialization = false;
+  FLAG_function_context_specialization = false;
   FLAG_always_opt = true;
   const char* flag = "--turbo-filter=foo";
   FlagList::SetFlagsFromString(flag, StrLength(flag));