Added namespaces in the newly C++ified AEC code

webrtc/modules/audio_processing/aec/aec_core_internal.h

Index: webrtc/modules/audio_processing/aec/aec_core_internal.h
diff --git a/webrtc/modules/audio_processing/aec/aec_core_internal.h b/webrtc/modules/audio_processing/aec/aec_core_internal.h
index b2e7301724d5f7dd886f300299f07bfa978a3e6d..b13c077bd711f3eb38732c3a81f68fd8e3d9b6eb 100644
--- a/webrtc/modules/audio_processing/aec/aec_core_internal.h
+++ b/webrtc/modules/audio_processing/aec/aec_core_internal.h
@@ -19,6 +19,8 @@ extern "C" {
 #include "webrtc/modules/audio_processing/aec/aec_core.h"
 #include "webrtc/typedefs.h"
 
+namespace webrtc {
+
 // Number of partitions for the extended filter mode. The first one is an enum
 // to be used in array declarations, as it represents the maximum filter length.
 enum { kExtendedNumPartitions = 32 };
@@ -227,4 +229,6 @@ extern WebRtcAecStoreAsComplex WebRtcAec_StoreAsComplex;
 typedef void (*WebRtcAecWindowData)(float* x_windowed, const float* x);
 extern WebRtcAecWindowData WebRtcAec_WindowData;
 
+}  // namespace webrtc
+
 #endif  // WEBRTC_MODULES_AUDIO_PROCESSING_AEC_AEC_CORE_INTERNAL_H_