Make subpel_avg_variance unit-test's input aligned

Make test input aligned, then jnt_comp's subpel_avg_variance simd
implementations pass unit tests.

Change-Id: Ic85442f3252ba4e8707e35fbd6344fd662aafd74
diff --git a/test/variance_test.cc b/test/variance_test.cc
index cf63109..3d88016 100644
--- a/test/variance_test.cc
+++ b/test/variance_test.cc
@@ -592,7 +592,8 @@
     if (!use_high_bit_depth()) {
       src_ = reinterpret_cast<uint8_t *>(aom_memalign(16, block_size()));
       sec_ = reinterpret_cast<uint8_t *>(aom_memalign(16, block_size()));
-      ref_ = new uint8_t[block_size() + width() + height() + 1];
+      ref_ = reinterpret_cast<uint8_t *>(
+          aom_memalign(16, block_size() + width() + height() + 1));
     } else {
       src_ = CONVERT_TO_BYTEPTR(reinterpret_cast<uint16_t *>(
           aom_memalign(16, block_size() * sizeof(uint16_t))));
@@ -609,7 +610,7 @@
   virtual void TearDown() {
     if (!use_high_bit_depth()) {
       aom_free(src_);
-      delete[] ref_;
+      aom_free(ref_);
       aom_free(sec_);
     } else {
       aom_free(CONVERT_TO_SHORTPTR(src_));