Force a flush of drawing to the widget when a dialog is shown.

BUG=823353
TEST=as in bug

Change-Id: I5da777068fc29c5638ef02d50e59d5d7b2729260
Reviewed-on: https://chromium-review.googlesource.com/971661
Reviewed-by: Ken Buchanan <kenrb@chromium.org>
Commit-Queue: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#544518}
void RenderWidgetHostImpl::NotifyScreenInfoChanged() {
  WasResized();

  if (touch_emulator_) {
    touch_emulator_->SetDeviceScaleFactor(GetScaleFactorForView(view_.get()));
  }
}

void RenderWidgetHostImpl::NotifyScreenInfoChanged() {
  WasResized();

  if (touch_emulator_) {
    touch_emulator_->SetDeviceScaleFactor(GetScaleFactorForView(view_.get()));
  }
}
