Roll HarfBuzz to 1.3.0

third_party/harfbuzz-ng/src/hb-buffer.cc

Index: third_party/harfbuzz-ng/src/hb-buffer.cc
diff --git a/third_party/harfbuzz-ng/src/hb-buffer.cc b/third_party/harfbuzz-ng/src/hb-buffer.cc
index 406db9c84fce18fb1b0b88a53e161bac7f9a8e53..3940a3dbf8ecd122f86c3fbb2472b21ecfea0afa 100644
--- a/third_party/harfbuzz-ng/src/hb-buffer.cc
+++ b/third_party/harfbuzz-ng/src/hb-buffer.cc
@@ -52,7 +52,7 @@
  *
  * Checks the equality of two #hb_segment_properties_t's.
  *
- * Return value: (transfer full):
+ * Return value:
  * %true if all properties of @a equal those of @b, false otherwise.
  *
  * Since: 0.9.7
@@ -183,6 +183,12 @@ hb_buffer_t::shift_forward (unsigned int count)
   if (unlikely (!ensure (len + count))) return false;
 
   memmove (info + idx + count, info + idx, (len - idx) * sizeof (info[0]));
+  if (idx + count > len)
+  {
+    /* Under memory failure we might expose this area.  At least
+     * clean it up.  Oh well... */
+    memset (info + len, 0, (idx + count - len) * sizeof (info[0]));
+  }
   len += count;
   idx += count;
 
@@ -426,6 +432,8 @@ hb_buffer_t::move_to (unsigned int i)
     /* Tricky part: rewinding... */
     unsigned int count = out_len - i;
 
+    /* This will blow in our face if memory allocation fails later
+     * in this same lookup... */
     if (unlikely (idx < count && !shift_forward (count + 32))) return false;
 
     assert (idx >= count);