Fix build break

SocketStream.cpp:135:33: error: 'nullptr' was not declared in this scope

Test: build
Change-Id: I015e35f7fab3b2f5a1edc4dff056716e1f13c463
Signed-off-by: Roman Kiryanov <rkir@google.com>
diff --git a/shared/OpenglCodecCommon/SocketStream.cpp b/shared/OpenglCodecCommon/SocketStream.cpp
index 067a75f..d6d31c0 100644
--- a/shared/OpenglCodecCommon/SocketStream.cpp
+++ b/shared/OpenglCodecCommon/SocketStream.cpp
@@ -132,7 +132,7 @@
 
 const unsigned char *SocketStream::commitBufferAndReadFully(size_t size, void *buf, size_t len)
 {
-    return commitBuffer(size) ? nullptr : readFully(buf, len);
+    return commitBuffer(size) ? NULL : readFully(buf, len);
 }
 
 const unsigned char *SocketStream::read( void *buf, size_t *inout_len)