Make V4L2CaptureDelegate non-ref-counted

media/capture/video/linux/v4l2_capture_delegate.cc

Index: media/capture/video/linux/v4l2_capture_delegate.cc
diff --git a/media/capture/video/linux/v4l2_capture_delegate.cc b/media/capture/video/linux/v4l2_capture_delegate.cc
index 2f16c203996b82851c6181e67ac4a3f07b96c8a6..baa2e9f1f30f821fc8c9fd6c9bd8c7077ccf44f1 100644
--- a/media/capture/video/linux/v4l2_capture_delegate.cc
+++ b/media/capture/video/linux/v4l2_capture_delegate.cc
@@ -506,7 +506,8 @@ void V4L2CaptureDelegate::AllocateAndStart(
 
   // Post task to start fetching frames from v4l2.
   v4l2_task_runner_->PostTask(
-      FROM_HERE, base::Bind(&V4L2CaptureDelegate::DoCapture, this));
+      FROM_HERE,
+      base::Bind(&V4L2CaptureDelegate::DoCapture, base::Unretained(this)));

[mcasas, 2017/04/11 17:17:34]

How would you guarantee that |this| is alive
when this Task gets scheduled, if V4L2CaptureDelegate
is "created and destroyed on the owner's thread" [1]
which is, presumably, different from 
|v4l2_task_runner_| ?

[1]
https://cs.chromium.org/chromium/src/media/capture/video/linux/v4l2_capture_d...

[Chandan, 2017/04/11 19:46:43]

Need to use weak pointer then? What do you suggest?

 }
 
 void V4L2CaptureDelegate::StopAndDeAllocate() {
@@ -820,7 +821,8 @@ void V4L2CaptureDelegate::DoCapture() {
   }
 
   v4l2_task_runner_->PostTask(
-      FROM_HERE, base::Bind(&V4L2CaptureDelegate::DoCapture, this));
+      FROM_HERE,
+      base::Bind(&V4L2CaptureDelegate::DoCapture, base::Unretained(this)));
 }
 
 void V4L2CaptureDelegate::SetErrorState(