Bug 1344653 - Update cubeb from upstream to a3c012f. r=kinetik

MozReview-Commit-ID: 3jQt8zdukUm

media/libcubeb/README_MOZILLA

@@ -5,4 +5,4 @@ Makefile.in build files for the Mozilla build system.
 
 The cubeb git repository is: git://github.com/kinetiknz/cubeb.git
 
-The git commit ID used was 0753297e4c881c4adf900b6c14af3d52a2a7eb2a (2017-03-02 15:13:01 +1300)
+The git commit ID used was a3c012fd29bf088d0fc006932b48080cb1f5d9c2 (2017-03-06 14:15:22 +1300)

media/libcubeb/src/cubeb_wasapi.cpp

@@ -1609,7 +1609,7 @@ int setup_wasapi_stream(cubeb_stream * stm)
     // is available when calling into the resampler to call the callback: the input
     // refill event will be set shortly after to compensate for this lack of data.
     // In debug, four buffers are used, to avoid tripping up assertions down the line.
-#if !defined(NDEBUG)
+#if !defined(DEBUG)
     const int silent_buffer_count = 2;
 #else
     const int silent_buffer_count = 4;