[wasm] Allow --turbo-stats to collect wasm compilation info.

src/flag-definitions.h

Index: src/flag-definitions.h
diff --git a/src/flag-definitions.h b/src/flag-definitions.h
index da231938450460e27c9d526c87a7d810027ad831..41e99466de22bfdbbd27e17868f1895a81d57649 100644
--- a/src/flag-definitions.h
+++ b/src/flag-definitions.h
@@ -528,6 +528,8 @@ DEFINE_BOOL(wasm_disable_structured_cloning, false,
             "disable WASM structured cloning")
 DEFINE_INT(wasm_num_compilation_tasks, 10,
            "number of parallel compilation tasks for wasm")
+// Parallel compilation confuses turbo_stats, force single threaded.
+DEFINE_VALUE_IMPLICATION(turbo_stats, wasm_num_compilation_tasks, 0)
 DEFINE_UINT(wasm_max_mem_pages, v8::internal::wasm::kV8MaxWasmMemoryPages,
             "maximum memory size of a wasm instance")
 DEFINE_UINT(wasm_max_table_size, v8::internal::wasm::kV8MaxWasmTableSize,