Use Value::Take...() in /pdf

Refactor to use the new base::Value
TakeString/TakeDict/TakeList methods that transfer ownership
in a clearer way and allow clang-tidy catch misuses.

This CL was uploaded by git cl split.

R=nigi@chromium.org

Bug: 1360570
Change-Id: Ib6931e28ed8fdeb5d0acc987b12c67d12d554c92
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3913062
Reviewed-by: Nigi <nigi@chromium.org>
Commit-Queue: Maksim Ivanov <emaxx@chromium.org>
Auto-Submit: Maksim Ivanov <emaxx@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1051999}

pdf/post_message_receiver.cc

@@ -129,7 +129,7 @@ void PostMessageReceiver::PostMessage(v8::Local<v8::Value> message) {
 
   client_task_runner_->PostTask(
       FROM_HERE, base::BindOnce(&Client::OnMessage, client_,
-                                std::move(converted_message->GetDict())));
+                                std::move(*converted_message).TakeDict()));
 }
 
 }  // namespace chrome_pdf