Fixed native crash observed on L3 devices by Jeff Tinker.

Change-Id: If78b7e9b5b5f4b87c5b2c55f75a00704e8536ce6
related-to-bug: 5952202

proprietary/wvm/WVMExtractorImpl.cpp

@@ -41,7 +41,7 @@ static int _cb2(char *in, char *out, int length, char *iv)
 
     if (sDrmManagerClient != NULL) {
         DrmBuffer encryptedDrmBuffer(in, length);
-        DrmBuffer ivBuffer(iv, length);
+        DrmBuffer ivBuffer(iv, (iv? AES_BLOCK_SIZE: 0));
 
         DrmBuffer decryptedDrmBuffer(out, length);
         DrmBuffer *decryptedDrmBufferPtr = &decryptedDrmBuffer;