Inherit the navigation initiator when navigating instead of the parent/opener

Spec PR: https://github.com/w3c/webappsec-csp/pull/358

Bug: 905301, 894228, 836148
Change-Id: I43ada2266d42d1cd56dbe3c6dd89d115e878a83a
Reviewed-on: https://chromium-review.googlesource.com/c/1314633
Commit-Queue: Andy Paicu <andypaicu@chromium.org>
Reviewed-by: Mike West <mkwst@chromium.org>
Cr-Commit-Position: refs/heads/master@{#610850}
bool ContentSecurityPolicy::AllowEval(
    ScriptState* script_state,
    SecurityViolationReportingPolicy reporting_policy,
    ContentSecurityPolicy::ExceptionStatus exception_status,
    const String& script_content) const {
  bool is_allowed = true;
  for (const auto& policy : policies_) {
    is_allowed &= policy->AllowEval(script_state, reporting_policy,
                                    exception_status, script_content);
  }
  return is_allowed;
}

bool ContentSecurityPolicy::AllowEval(
    ScriptState* script_state,
    SecurityViolationReportingPolicy reporting_policy,
    ContentSecurityPolicy::ExceptionStatus exception_status,
    const String& script_content) const {
  bool is_allowed = true;
  for (const auto& policy : policies_) {
    is_allowed &= policy->AllowEval(script_state, reporting_policy,
                                    exception_status, script_content);
  }
  return is_allowed;
}
