conditional_focus_capturing_page.html

<html>
  <head>
    <title>Conditional Focus Test - Capturing Page</title>
    <link rel="icon" href="data:," />
    <script>
      "use strict";

      let mediaStreamKeepAlive;  // Keeps the capture alive.

      // Calls getDisplayMedia().
      // Calling with |busyWaitMs| set to a positive value leads to hogging
      // the CPU for that long *before* calling setFocusBehavior().
      // Then:
      // * If (focusCallValue == ''), don't call setFocusBehavior().
      // * If (focusCallValue != ''), call setFocusBehavior(focusCallValue).
      // * If |onCorrectMicrotask|, setFocusBehavior() is called on the
      //   microtask on which getDisplayMedia's Promise was resolved.
      //   Otherwise, it is scheduled to be called in a later task.
      async function captureOtherTab(busyWaitMs, focusCallValue, onCorrectMicrotask) {
        try {
          const controller = new CaptureController();
          const mediaStream = await navigator.mediaDevices.getDisplayMedia({ controller });
          if (onCorrectMicrotask) {
            return handleCaptureSuccess(mediaStream, busyWaitMs, focusCallValue, controller);
          } else {
            return new Promise(resolve => {
              setTimeout(resolve, 0);
            }).then(() => handleCaptureSuccess(mediaStream, busyWaitMs, focusCallValue, controller));
          }
        } catch (error) {
          return "capture-failure";
        }
      }

      function busyWait(durationMs) {
        const targetTime = new Date().getTime() + durationMs;
        while (new Date().getTime() < targetTime) {
          // Busy-wait.
        }
      }

      function handleCaptureSuccess(mediaStream, busyWaitMs, focusCallValue, controller) {
        mediaStreamKeepAlive = mediaStream;

        if (busyWaitMs > 0) {
          busyWait(busyWaitMs);
        }

        if (focusCallValue) {
          try {
            controller.setFocusBehavior(focusCallValue);
          } catch (error) {
            return `${error}`;
          }
        }

        // Allow the microtask to fire before unblocking the test.
        return new Promise(resolve => {
          setTimeout(resolve);
        }).then(() => "capture-success");
      }

      // Calls setFocusBehavior(focusCallValueBeforeCapture) before
      // getDisplayMedia({ controller }). Then
      // if (focusCallValueAfterCapture != '') call
      // setFocusBehavior(focusCallValueAfterCapture) on the microtask on which
      // getDisplayMedia's Promise was resolved.
      async function callSetFocusBehaviorBeforeCapture(focusCallValueBeforeCapture, focusCallValueAfterCapture) {
        try {
          const controller = new CaptureController();
          controller.setFocusBehavior(focusCallValueBeforeCapture);
          await navigator.mediaDevices.getDisplayMedia({ controller });
          if (focusCallValueAfterCapture) {
            controller.setFocusBehavior(focusCallValueAfterCapture);
          }
          return "capture-success";
        } catch (error) {
          return `${error}`;
        }
      }
    </script>
  </head>
  <body>
    <h1>Conditional Focus Test - Capturing Page</h1>
  </body>
</html>
chromium/chrome/test/data/webrtc/conditional_focus_capturing_page.html
