Move enable_webrtc to a buildflag header.

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
index c8c5198620e72f76b7f8e30d13839aedcd540eea..eeb45e72b5bca0d66caeca94aba6fa82a08a5181 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -132,6 +132,7 @@
 #include "ipc/ipc_channel_mojo.h"
 #include "ipc/ipc_platform_file.h"
 #include "media/base/media.h"
+#include "media/media_features.h"
 #include "media/renderers/gpu_video_accelerator_factories.h"
 #include "mojo/common/common_type_converters.h"
 #include "mojo/public/cpp/bindings/strong_binding.h"
@@ -185,7 +186,7 @@
 #include <objbase.h>
 #endif
 
-#if defined(ENABLE_WEBRTC)
+#if BUILDFLAG(ENABLE_WEBRTC)
 #include "content/renderer/media/aec_dump_message_filter.h"
 #include "content/renderer/media/peer_connection_tracker.h"
 #include "content/renderer/media/rtc_peer_connection_handler.h"
@@ -696,7 +697,7 @@ void RenderThreadImpl::Init(
   browser_plugin_manager_.reset(new BrowserPluginManager());
   AddObserver(browser_plugin_manager_.get());
 
-#if defined(ENABLE_WEBRTC)
+#if BUILDFLAG(ENABLE_WEBRTC)
   peer_connection_tracker_.reset(new PeerConnectionTracker());
   AddObserver(peer_connection_tracker_.get());
 
@@ -711,7 +712,7 @@ void RenderThreadImpl::Init(
 
   AddFilter(aec_dump_message_filter_.get());
 
-#endif  // defined(ENABLE_WEBRTC)
+#endif  // BUILDFLAG(ENABLE_WEBRTC)
 
   audio_input_message_filter_ = new AudioInputMessageFilter(GetIOTaskRunner());
   AddFilter(audio_input_message_filter_.get());
@@ -934,7 +935,7 @@ void RenderThreadImpl::Shutdown() {
   RemoveFilter(audio_input_message_filter_.get());
   audio_input_message_filter_ = nullptr;
 
-#if defined(ENABLE_WEBRTC)
+#if BUILDFLAG(ENABLE_WEBRTC)
   RTCPeerConnectionHandler::DestructAllHandlers();
   // |peer_connection_factory_| cannot be deleted until after the main message
   // loop has been destroyed.  This is because there may be pending tasks that
@@ -2077,7 +2078,7 @@ RenderThreadImpl::RequestCopyOfOutputForLayoutTest(
 
 blink::WebMediaStreamCenter* RenderThreadImpl::CreateMediaStreamCenter(
     blink::WebMediaStreamCenterClient* client) {
-#if defined(ENABLE_WEBRTC)
+#if BUILDFLAG(ENABLE_WEBRTC)
   if (!media_stream_center_) {
     media_stream_center_ = GetContentClient()->renderer()
         ->OverrideCreateWebMediaStreamCenter(client);
@@ -2091,7 +2092,7 @@ blink::WebMediaStreamCenter* RenderThreadImpl::CreateMediaStreamCenter(
   return media_stream_center_;
 }
 
-#if defined(ENABLE_WEBRTC)
+#if BUILDFLAG(ENABLE_WEBRTC)
 PeerConnectionDependencyFactory*
 RenderThreadImpl::GetPeerConnectionDependencyFactory() {
   return peer_connection_factory_.get();