Implement writing mic audio input data to file for debugging purposes.

content/renderer/media/aec_dump_message_filter.cc

Index: content/renderer/media/aec_dump_message_filter.cc
diff --git a/content/renderer/media/aec_dump_message_filter.cc b/content/renderer/media/aec_dump_message_filter.cc
index 3788e18df30eb3226aacbf3732e199088afba505..76f104ca4592496237b0a7d7a2009f39eaee35f8 100644
--- a/content/renderer/media/aec_dump_message_filter.cc
+++ b/content/renderer/media/aec_dump_message_filter.cc
@@ -22,7 +22,7 @@ AecDumpMessageFilter::AecDumpMessageFilter(
     const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
     const scoped_refptr<base::SingleThreadTaskRunner>& main_task_runner)
     : sender_(NULL),
-      delegate_id_counter_(0),
+      delegate_id_counter_(1),

[tommi (sloooow) - chröme, 2015/08/31 17:19:07]

why this change?

[Henrik Grunell, 2015/09/04 12:37:37]

I wanted it to have the same start ID as input streams. The stream and AEC dump
delegate IDs don't map to each other, but in most cases people will have one tab
that renders an AEC dump file and an input audio file. Seems odd that one file
would have ".0" and one ".1" in its name.

       io_task_runner_(io_task_runner),
       main_task_runner_(main_task_runner) {
   DCHECK(!g_filter);