Add missing interface methods.

DesktopCapturer includes a few methods that are not pure virtual because
they were added after implementions existed in Chromium. The intent was
to implement them in Chromium and then make them pure virtual, but that
never happened, which caused a bug when DesktopAndCursorComposer did not
delegate source-selection methods to the underlying capturer.

This CL adds the missing methods to a couple of simple pass-through
capturers; I will follow up with the necessary implementations for other
capturers once I've fixed the underlying remoting bug.

Change-Id: Icb3914a3cb3116878f57a9f685163c7670c1f89b
Bug: webrtc:11370
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/168780
Reviewed-by: Sergey Ulanov <sergeyu@chromium.org>
Commit-Queue: Jamie Walch <jamiewalch@chromium.org>
Cr-Commit-Position: refs/heads/master@{#30550}

modules/desktop_capture/blank_detector_desktop_capturer_wrapper.cc

@@ -63,6 +63,10 @@ bool BlankDetectorDesktopCapturerWrapper::FocusOnSelectedSource() {
   return capturer_->FocusOnSelectedSource();
 }
 
+bool BlankDetectorDesktopCapturerWrapper::IsOccluded(const DesktopVector& pos) {
+  return capturer_->IsOccluded(pos);
+}
+
 void BlankDetectorDesktopCapturerWrapper::OnCaptureResult(
     Result result,
     std::unique_ptr<DesktopFrame> frame) {

modules/desktop_capture/blank_detector_desktop_capturer_wrapper.h

@@ -46,6 +46,7 @@ class BlankDetectorDesktopCapturerWrapper final
   bool GetSourceList(SourceList* sources) override;
   bool SelectSource(SourceId id) override;
   bool FocusOnSelectedSource() override;
+  bool IsOccluded(const DesktopVector& pos) override;
 
  private:
   // DesktopCapturer::Callback interface.

modules/desktop_capture/desktop_and_cursor_composer.cc

@@ -187,6 +187,22 @@ void DesktopAndCursorComposer::SetExcludedWindow(WindowId window) {
   desktop_capturer_->SetExcludedWindow(window);
 }
 
+bool DesktopAndCursorComposer::GetSourceList(SourceList* sources) {
+  return desktop_capturer_->GetSourceList(sources);
+}
+
+bool DesktopAndCursorComposer::SelectSource(SourceId id) {
+  return desktop_capturer_->SelectSource(id);
+}
+
+bool DesktopAndCursorComposer::FocusOnSelectedSource() {
+  return desktop_capturer_->FocusOnSelectedSource();
+}
+
+bool DesktopAndCursorComposer::IsOccluded(const DesktopVector& pos) {
+  return desktop_capturer_->IsOccluded(pos);
+}
+
 void DesktopAndCursorComposer::OnCaptureResult(
     DesktopCapturer::Result result,
     std::unique_ptr<DesktopFrame> frame) {

modules/desktop_capture/desktop_and_cursor_composer.h

@@ -53,6 +53,10 @@ class RTC_EXPORT DesktopAndCursorComposer
       std::unique_ptr<SharedMemoryFactory> shared_memory_factory) override;
   void CaptureFrame() override;
   void SetExcludedWindow(WindowId window) override;
+  bool GetSourceList(SourceList* sources) override;
+  bool SelectSource(SourceId id) override;
+  bool FocusOnSelectedSource() override;
+  bool IsOccluded(const DesktopVector& pos) override;
 
   // MouseCursorMonitor::Callback interface.
   void OnMouseCursor(MouseCursor* cursor) override;