V8ValueConverter::ToV8Value should not trigger setters

BUG=606390

Review URL: https://codereview.chromium.org/1918793003

Cr-Commit-Position: refs/heads/master@{#390045}
    ~Level() {
      state_->max_recursion_depth_++;
    }

    ~Level() {
      state_->max_recursion_depth_++;
    }
