Fix use of history timers in background threads.

src/compiler/wasm-compiler.h

Index: src/compiler/wasm-compiler.h
diff --git a/src/compiler/wasm-compiler.h b/src/compiler/wasm-compiler.h
index f88659b2182b9454b2eb1db04eb7c9e245af214b..b88be4d3f4558dc1fe1eec92c6eb3620841dd57e 100644
--- a/src/compiler/wasm-compiler.h
+++ b/src/compiler/wasm-compiler.h
@@ -48,10 +48,9 @@ namespace compiler {
 class WasmCompilationUnit final {
  public:
   WasmCompilationUnit(Isolate* isolate, wasm::ModuleBytesEnv* module_env,
-                      const wasm::WasmFunction* function, bool is_sync = true);
+                      const wasm::WasmFunction* function);
   WasmCompilationUnit(Isolate* isolate, wasm::ModuleEnv* module_env,
-                      wasm::FunctionBody body, wasm::WasmName name, int index,
-                      bool is_sync = true);
+                      wasm::FunctionBody body, wasm::WasmName name, int index);
 
   int func_index() const { return func_index_; }
 
@@ -74,7 +73,6 @@ class WasmCompilationUnit final {
   wasm::ModuleEnv* module_env_;
   wasm::FunctionBody func_body_;
   wasm::WasmName func_name_;
-  bool is_sync_;
   // The graph zone is deallocated at the end of ExecuteCompilation by virtue of
   // it being zone allocated.
   JSGraph* jsgraph_ = nullptr;