Inherit CSP when we inherit the security origin

This prevents attacks that use main window navigation to get out of the
existing csp constraints such as the related bug

Bug: 747847
Change-Id: I1e57b50da17f65d38088205b0a3c7c49ef2ae4d8
Reviewed-on: https://chromium-review.googlesource.com/592027
Reviewed-by: Mike West <mkwst@chromium.org>
Commit-Queue: Andy Paicu <andypaicu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#492333}
void Document::MaybeQueueSendDidEditFieldInInsecureContext() {
  if (logged_field_edit_ || sensitive_input_edited_task_.IsActive() ||
      IsSecureContext()) {
    return;
  }
  logged_field_edit_ = true;
  sensitive_input_edited_task_ =
      TaskRunnerHelper::Get(TaskType::kUserInteraction, this)
          ->PostCancellableTask(
              BLINK_FROM_HERE,
              WTF::Bind(&Document::SendDidEditFieldInInsecureContext,
                        WrapWeakPersistent(this)));
}

void Document::MaybeQueueSendDidEditFieldInInsecureContext() {
  if (logged_field_edit_ || sensitive_input_edited_task_.IsActive() ||
      IsSecureContext()) {
    return;
  }
  logged_field_edit_ = true;
  sensitive_input_edited_task_ =
      TaskRunnerHelper::Get(TaskType::kUserInteraction, this)
          ->PostCancellableTask(
              BLINK_FROM_HERE,
              WTF::Bind(&Document::SendDidEditFieldInInsecureContext,
                        WrapWeakPersistent(this)));
}
