CroppedDesktopFrame wrongly sets the DesktopFrame::size()

Bug: chromium:761703
Change-Id: I2888ccbe602b65e8e61e9dfccf54b5bb6701746d
Reviewed-on: https://chromium-review.googlesource.com/651607
Reviewed-by: Jamie Walch <jamiewalch@chromium.org>
Commit-Queue: Zijie He <zijiehe@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#19699}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 51ce0c0d2fd5f633afb9d387cdecc3412bf8f5bb
diff --git a/modules/desktop_capture/cropped_desktop_frame.cc b/modules/desktop_capture/cropped_desktop_frame.cc
index 67f03e7..a76a3e7 100644
--- a/modules/desktop_capture/cropped_desktop_frame.cc
+++ b/modules/desktop_capture/cropped_desktop_frame.cc
@@ -48,7 +48,7 @@
 
 CroppedDesktopFrame::CroppedDesktopFrame(std::unique_ptr<DesktopFrame> frame,
                                          const DesktopRect& rect)
-    : DesktopFrame(frame->size(),
+    : DesktopFrame(rect.size(),
                    frame->stride(),
                    frame->GetFrameDataAtPos(rect.top_left()),
                    frame->shared_memory()),