src.chromium.org/viewvc/chrome/trunk/src/chrome/renderer/print_web_view_helper_win.cc?revision=27421&view=markup&pathrev=31561
По этому адресу видим:
// TODO(maruel): Move this out of platform specific code.
// Check if there is script repeatedly trying to print and ignore it if too
// frequent. We use exponential wait time so for a page that calls print() in
// a loop the user will need to cancel the print dialog after 2 seconds, 4
// seconds, 8, ... up to the maximum of 2 minutes.
// This gives the user time to navigate from the page.
if (script_initiated && (user_cancelled_scripted_print_count_ > 0)) {
base::TimeDelta diff = base::Time::Now() - last_cancelled_script_print_;
int min_wait_seconds = std::min(
kMinSecondsToIgnoreJavascriptInitiatedPrint <<
(user_cancelled_scripted_print_count_ - 1),
kMaxSecondsToIgnoreJavascriptInitiatedPrint);
if (diff.InSeconds() < min_wait_seconds) {
WebString message(WebString::fromUTF8(
"Ignoring too frequent calls to print()."));
frame->addMessageToConsole(WebConsoleMessage(
WebConsoleMessage::LevelWarning,
message));
return;
}
}
Как я понял — там жестко забита задержка…
