Bug 1978645 - Part 3: Remove malloc block cache and nursery trailer tracking r=jseward

Differential Revision: https://phabricator.services.mozilla.com/D265785

Author: jonco3

js/public/GCAPI.h

@@ -656,7 +656,7 @@ namespace JS {
   D(FULL_CELL_PTR_STR_BUFFER, 28)                                      \
   D(TOO_MUCH_JIT_CODE, 29)                                             \
   D(FULL_CELL_PTR_BIGINT_BUFFER, 30)                                   \
-  D(NURSERY_TRAILERS, 31)                                              \
+  D(UNUSED4, 31)                                                       \
   D(NURSERY_MALLOC_BUFFERS, 32)                                        \
                                                                        \
   /*                                                                   \

js/src/ds/PointerAndUint7.h

@@ -160,7 +160,6 @@ enum class GCAbortReason {
   _(XDRBufferElements)                     \
   _(GlobalObjectData)                      \
   _(ProxyExternalValueArray)               \
-  _(WasmTrailerBlock)                      \
   _(GraphLoadingStateRecord)
 
 #define JS_FOR_EACH_MEMORY_USE(_)  \