Android: not to pause screen capture when Chrome is put to background

content/renderer/render_view_impl.cc

Index: content/renderer/render_view_impl.cc
diff --git a/content/renderer/render_view_impl.cc b/content/renderer/render_view_impl.cc
index 0c57eceedfeb4a5ff928e02c11661de31f1f4558..ddec70d698a98c3d9fe08667128f167941f719b2 100644
--- a/content/renderer/render_view_impl.cc
+++ b/content/renderer/render_view_impl.cc
@@ -84,6 +84,7 @@
 #include "content/renderer/input/input_handler_manager.h"
 #include "content/renderer/internal_document_state_data.h"
 #include "content/renderer/media/audio_device_factory.h"
+#include "content/renderer/media/media_stream_dispatcher.h"
 #include "content/renderer/media/video_capture_impl_manager.h"
 #include "content/renderer/navigation_state_impl.h"
 #include "content/renderer/render_frame_impl.h"
@@ -2278,8 +2279,8 @@ void RenderViewImpl::Close() {
 
 void RenderViewImpl::OnPageWasHidden() {
 #if defined(OS_ANDROID) && BUILDFLAG(ENABLE_WEBRTC)

[miu, 2017/03/22 23:09:43]

Why does BUILDFLAG(ENABLE_WEBRTC) matter? This logic should be applicable to ALL
remoting technologies. Let's change this to:

  #if defined(OS_ANDROID)
    SuspendVideoCaptureDevices();
  #if BUILDFLAG(ENABLE_WEBRTC)
    ...speech recog stuff...
  #endif
  #endif

[braveyao, 2017/03/23 03:44:20]

Done.

-  RenderThreadImpl::current()->video_capture_impl_manager()->
-      SuspendDevices(true);
+  SuspendVideoCaptureDevices(true);
+
   if (speech_recognition_dispatcher_)
     speech_recognition_dispatcher_->AbortAllRecognitions();
 #endif
@@ -2298,8 +2299,7 @@ void RenderViewImpl::OnPageWasHidden() {
 
 void RenderViewImpl::OnPageWasShown() {
 #if defined(OS_ANDROID) && BUILDFLAG(ENABLE_WEBRTC)

[miu, 2017/03/22 23:09:43]

Remove the BUILDFLAG(ENABLE_WEBRTC) part.

[braveyao, 2017/03/23 03:44:20]

Done.

-  RenderThreadImpl::current()->video_capture_impl_manager()->
-      SuspendDevices(false);
+  SuspendVideoCaptureDevices(false);
 #endif
 
   if (webview()) {
@@ -2568,6 +2568,27 @@ bool RenderViewImpl::didTapMultipleTargets(
 
   return handled;
 }
+
+void RenderViewImpl::SuspendVideoCaptureDevices(bool suspend) {
+  if (!main_render_frame_)
+    return;
+
+  MediaStreamDispatcher* media_stream_dispatcher =
+      main_render_frame_->GetMediaStreamDispatcher();
+  if (media_stream_dispatcher) {

[miu, 2017/03/22 23:09:43]

nit:

  if (!media_stream_dispatcher)
    return;

  ... rest of code one indent level less...

[braveyao, 2017/03/23 03:44:20]

Done.

+    StreamDeviceInfoArray video_array;
+    media_stream_dispatcher->GetVideoCaptureDevices(&video_array);
+    for (const StreamDeviceInfo& device_info : video_array) {
+      if (suspend) {

[miu, 2017/03/22 23:09:43]

See comments in header file about just having two methods instead of this bool
and the extra run-time cost here.

[braveyao, 2017/03/23 03:44:20]

Done.

+        RenderThreadImpl::current()->video_capture_impl_manager()->Suspend(
+            device_info.session_id);
+      } else {
+        RenderThreadImpl::current()->video_capture_impl_manager()->Resume(
+            device_info.session_id);
+      }
+    }
+  }
+}
 #endif  // defined(OS_ANDROID)
 
 unsigned RenderViewImpl::GetLocalSessionHistoryLengthForTesting() const {