Fix array declarations in aec_core.c

Was causing warnings in Chromium such as:

warning C4742: 'WebRtcAec_overDriveCurve' has different alignment in 'E:\src\buildbot\build\slave\fake_slave\build\src\third_party\webrtc\modules\audio_processing\aec\aec_core_sse2.c' and 'E:\src\buildbot\build\slave\fake_slave\build\src\third_party\webrtc\modules\audio_processing\aec\aec_core.c': 4 and 16
warning C4744: 'WebRtcAec_overDriveCurve' has different type in 'E:\src\buildbot\build\slave\fake_slave\build\src\third_party\webrtc\modules\audio_processing\aec\aec_core_sse2.c' and 'E:\src\buildbot\build\slave\fake_slave\build\src\third_party\webrtc\modules\audio_processing\aec\aec_core.c': 'array (260 bytes)' and '__declspec(align(16)) array (260 bytes)'
warning C4742: 'WebRtcAec_weightCurve' has different alignment in 'E:\src\buildbot\build\slave\fake_slave\build\src\third_party\webrtc\modules\audio_processing\aec\aec_core_sse2.c' and 'E:\src\buildbot\build\slave\fake_slave\build\src\third_party\webrtc\modules\audio_processing\aec\aec_core.c': 4 and 16
warning C4744: 'WebRtcAec_weightCurve' has different type in 'E:\src\buildbot\build\slave\fake_slave\build\src\third_party\webrtc\modules\audio_processing\aec\aec_core_sse2.c' and 'E:\src\buildbot\build\slave\fake_slave\build\src\third_party\webrtc\modules\audio_processing\aec\aec_core.c': 'array (260 bytes)' and '__declspec(align(16)) array (260 bytes)'

BUG=https://code.google.com/p/chromium/issues/detail?id=336620
R=andrew@webrtc.org, cd@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/15869004

Patch from Sebastien Marchand <sebmarchand@chromium.org>.

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6525 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/audio_processing/aec/aec_core_sse2.c b/webrtc/modules/audio_processing/aec/aec_core_sse2.c
index 8d4afdb..1489d26 100644
--- a/webrtc/modules/audio_processing/aec/aec_core_sse2.c
+++ b/webrtc/modules/audio_processing/aec/aec_core_sse2.c
@@ -354,8 +354,8 @@
   return a_exp_b;
 }
 
-extern const float WebRtcAec_weightCurve[65];
-extern const float WebRtcAec_overDriveCurve[65];
+extern ALIGN16_BEG const float ALIGN16_END WebRtcAec_weightCurve[65];
+extern ALIGN16_BEG const float ALIGN16_END WebRtcAec_overDriveCurve[65];
 
 static void OverdriveAndSuppressSSE2(AecCore* aec,
                                      float hNl[PART_LEN1],