[api] Counters for WASM shared memory and threads opcodes

Note that this splits off counters added in
https://chromium-review.googlesource.com/c/v8/v8/+/1186343

R=ahaas@chromium.org

Bug: chromium:868844
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng
Change-Id: I263c63a51d8ce3418eacabb6beb11fa1b3dfaa96
Reviewed-on: https://chromium-review.googlesource.com/1186721Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55357}

include/v8.h

@@ -7433,6 +7433,8 @@ class V8_EXPORT Isolate {
     kDeoptimizerDisableSpeculation = 47,
     kArrayPrototypeSortJSArrayModifiedPrototype = 48,
     kFunctionTokenOffsetTooLongForToString = 49,
+    kWasmSharedMemory = 50,
+    kWasmThreadOpcodes = 51,
 
     // If you add new values here, you'll also need to update Chromium's:
     // web_feature.mojom, UseCounterCallback.cpp, and enums.xml. V8 changes to