Fixed window capute may end when window's full screen mode switchs on/off

webrtc/modules/desktop_capture/window_capturer_win.cc

Index: webrtc/modules/desktop_capture/window_capturer_win.cc
diff --git a/webrtc/modules/desktop_capture/window_capturer_win.cc b/webrtc/modules/desktop_capture/window_capturer_win.cc
index c0d71167a54d8ae99f602062764a59357dba9c84..69f74f48268718dd0c0587fa9401bc442cfd2dbb 100644
--- a/webrtc/modules/desktop_capture/window_capturer_win.cc
+++ b/webrtc/modules/desktop_capture/window_capturer_win.cc
@@ -156,15 +156,16 @@ void WindowCapturerWin::Capture(const DesktopRegion& region) {
     return;
   }
 
-  // Stop capturing if the window has been closed or hidden.
-  if (!IsWindow(window_) || !IsWindowVisible(window_)) {
+  // Stop capturing if the window has been closed.
+  if (!IsWindow(window_)) {
     callback_->OnCaptureCompleted(NULL);
     return;
   }
 
-  // Return a 1x1 black frame if the window is minimized, to match the behavior
-  // on Mac.
-  if (IsIconic(window_)) {
+  // Return a 1x1 black frame if the window is minimized to match the behavior
+  // on Mac, or if window is invisible. Window can be temporarily invisible

[Sergey Ulanov, 2015/11/09 21:27:40]

reword first sentence: 
// Return a 1x1 black frame if the window is minimized or invisible, to match
// behavior on mac

[GeorgeZ, 2015/11/09 21:59:06]

Done.

+  // during the transition of full screen mode on/off.
+  if (IsIconic(window_) || !IsWindowVisible(window_)) {
     BasicDesktopFrame* frame = new BasicDesktopFrame(DesktopSize(1, 1));
     memset(frame->data(), 0, frame->stride() * frame->size().height());