Use multiple shared memory buffers cyclically for audio capture.

content/renderer/pepper/pepper_platform_audio_input_impl.cc

Index: content/renderer/pepper/pepper_platform_audio_input_impl.cc
===================================================================
--- content/renderer/pepper/pepper_platform_audio_input_impl.cc	(revision 186364)
+++ content/renderer/pepper/pepper_platform_audio_input_impl.cc	(working copy)
@@ -66,7 +66,8 @@
 void PepperPlatformAudioInputImpl::OnStreamCreated(
     base::SharedMemoryHandle handle,
     base::SyncSocket::Handle socket_handle,
-    int length) {
+    int length,
+    int total_segments) {
 #if defined(OS_WIN)
   DCHECK(handle);
   DCHECK(socket_handle);
@@ -75,6 +76,8 @@
   DCHECK_NE(-1, socket_handle);
 #endif
   DCHECK(length);
+  // TODO(yzshen): Make use of circular buffer scheme. crbug.com/181449.
+  DCHECK_EQ(1, total_segments);
 
   if (base::MessageLoopProxy::current() != main_message_loop_proxy_) {
     // No need to check |shutdown_called_| here. If shutdown has occurred,
@@ -83,7 +86,7 @@
     main_message_loop_proxy_->PostTask(
         FROM_HERE,
         base::Bind(&PepperPlatformAudioInputImpl::OnStreamCreated, this,
-                   handle, socket_handle, length));
+                   handle, socket_handle, length, total_segments));
   } else {
     // Must dereference the client only on the main thread. Shutdown may have
     // occurred while the request was in-flight, so we need to NULL check.
@@ -117,7 +120,7 @@
                    this));
   } else {
     // We will be notified by OnStreamCreated().
-    ipc_->CreateStream(stream_id_, params_, device_id, false);
+    ipc_->CreateStream(stream_id_, params_, device_id, false, 1);
   }
 }
 
@@ -196,7 +199,7 @@
   if (!session_id) {
     // We will be notified by OnStreamCreated().
     ipc_->CreateStream(stream_id_, params_,
-        media::AudioManagerBase::kDefaultDeviceId, false);
+        media::AudioManagerBase::kDefaultDeviceId, false, 1);
   } else {
     // We will be notified by OnDeviceReady().
     ipc_->StartDevice(stream_id_, session_id);