cast: Support for low-latency interactive mode

content/browser/media/capture/cursor_renderer_aura.cc

Index: content/browser/media/capture/cursor_renderer_aura.cc
diff --git a/content/browser/media/capture/cursor_renderer_aura.cc b/content/browser/media/capture/cursor_renderer_aura.cc
index f2ce8aee50a37e7ca030d8c564f3b5fa78ad180c..84e9b31dfc6d52d26e4a84a71dbed186e18ad446 100644
--- a/content/browser/media/capture/cursor_renderer_aura.cc
+++ b/content/browser/media/capture/cursor_renderer_aura.cc
@@ -23,6 +23,10 @@ namespace content {
 
 namespace {
 
+// The time period within which a triggered UI event is considered
+// currently active.
+const int kTimePeriodUiEventMicros = 100000;  // 100 ms
+
 inline int clip_byte(int x) {
   return std::max(0, std::min(x, 255));
 }
@@ -53,6 +57,11 @@ base::WeakPtr<CursorRenderer> CursorRendererAura::GetWeakPtr() {
   return weak_factory_.GetWeakPtr();
 }
 
+bool CursorRendererAura::ui_event_detected() const {
+  return (tick_clock_->NowTicks() - last_time_ui_event_detected_) <
+         base::TimeDelta::FromMicroseconds(kTimePeriodUiEventMicros);
+}
+
 void CursorRendererAura::Clear() {
   last_cursor_ = ui::Cursor();
   window_size_when_cursor_last_updated_ = gfx::Size();
@@ -184,6 +193,11 @@ void CursorRendererAura::RenderOnVideoFrame(
   scaled_cursor_bitmap_.unlockPixels();
 }
 
+void CursorRendererAura::OnEvent(ui::Event* event) {
+  last_time_ui_event_detected_ = tick_clock_->NowTicks();
+  ui::EventHandler::OnEvent(event);
+}
+
 void CursorRendererAura::OnMouseEvent(ui::MouseEvent* event) {
   switch (event->type()) {
     case ui::ET_MOUSE_MOVED: