[wasm] Remove some small TODOs and small fixes.

src/wasm/wasm-module.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <functional>
 #include <memory>
 
 #include "src/code-stubs.h"
 #include "src/debug/interface-types.h"
 #include "src/frames-inl.h"
@@ skipping 340 matching lines @@
   DCHECK_EQ(code->kind() == Code::WASM_INTERPRETER_ENTRY ? 1 : 2,
             deopt_data->length());
   Object* weak_link = deopt_data->get(0);
   DCHECK(weak_link->IsWeakCell());
   WeakCell* cell = WeakCell::cast(weak_link);
   if (cell->cleared()) return nullptr;
   return WasmInstanceObject::cast(cell->value());
 }
 
 WasmModule::WasmModule(std::unique_ptr<Zone> owned)
-    : signature_zone(std::move(owned)), pending_tasks(new base::Semaphore(0)) {}
+    : signature_zone(std::move(owned)) {}
 
 WasmFunction* wasm::GetWasmFunctionForImportWrapper(Isolate* isolate,
                                                     Handle<Object> target) {
   if (target->IsJSFunction()) {
     Handle<JSFunction> func = Handle<JSFunction>::cast(target);
     if (func->code()->kind() == Code::JS_TO_WASM_FUNCTION) {
       auto exported = Handle<WasmExportedFunction>::cast(func);
       Handle<WasmInstanceObject> other_instance(exported->instance(), isolate);
       int func_index = exported->function_index();
       return &other_instance->module()->functions[func_index];
@@ skipping 755 matching lines @@
                                      callee_compiled->instruction_start());
     }
     DCHECK_EQ(non_compiled_functions.size(), idx);
   }
 
   Code* ret =
       Code::cast(compiled_module->code_table()->get(func_to_return_idx));
   DCHECK_EQ(Code::WASM_FUNCTION, ret->kind());
   return handle(ret, isolate);
 }