Ensure that default Huffman tables are initialized

This prevents a malformed motion-JPEG frame (MJPEG frames lack Huffman
tables) from causing the "fast path" of the Huffman decoder to read
uninitialized memory.  Essentially, this is doing the same thing for
MJPEG frames as 43d8cf4d4572fa50a37cccadbe71b9bee37de55d did for regular
images.

Cherry picked from upstream:
https://github.com/libjpeg-turbo/libjpeg-turbo/commit/a572622dd654305c86585724c2a1ea34e22c2103

BUG:27494207
BUG:27480923
Change-Id: I91f334b82290b009bc624b3d5f8a9b3021f34ea0
diff --git a/ChangeLog.txt b/ChangeLog.txt
index 5f9db11..49b760f 100644
--- a/ChangeLog.txt
+++ b/ChangeLog.txt
@@ -1,3 +1,31 @@
+1.4.3
+=====
+
+[1] Fixed a regression caused by 1.4.1[6] that prevented 32-bit and 64-bit
+libjpeg-turbo RPMs from being installed simultaneously on recent Red Hat/Fedora
+distributions.  This was due to the addition of a macro in jconfig.h that
+allows the Huffman codec to determine the word size at compile time.  Since
+that macro differs between 32-bit and 64-bit builds, this caused a conflict
+between the i386 and x86_64 RPMs (any differing files, other than executables,
+are not allowed when 32-bit and 64-bit RPMs are installed simultaneously.)
+Since the macro is used only internally, it has been moved into jconfigint.h.
+
+[2] Fixed an issue in the accelerated Huffman decoder that could have caused
+the decoder to read past the end of the input buffer when a malformed,
+specially-crafted JPEG image was being decompressed.  In prior versions of
+libjpeg-turbo, the accelerated Huffman decoder was invoked (in most cases) only
+if there were > 128 bytes of data in the input buffer.  However, it is possible
+to construct a JPEG image in which a single Huffman block is over 430 bytes
+long, so this version of libjpeg-turbo activates the accelerated Huffman
+decoder only if there are > 512 bytes of data in the input buffer.
+
+[3] Fixed a memory leak in tjunittest encountered when running the program
+with the -yuv option.
+
+[4] Fixed an issue whereby a malformed motion-JPEG frame could cause the "fast
+path" of libjpeg-turbo's Huffman decoder to read from uninitialized memory.
+
+
 1.4.2
 =====
 
diff --git a/jstdhuff.c b/jstdhuff.c
index b29e5ea..1264259 100644
--- a/jstdhuff.c
+++ b/jstdhuff.c
@@ -41,6 +41,7 @@
     ERREXIT(cinfo, JERR_BAD_HUFF_TABLE);
 
   MEMCOPY((*htblptr)->huffval, val, nsymbols * sizeof(UINT8));
+  MEMZERO(&((*htblptr)->huffval[nsymbols]), (256 - nsymbols) * sizeof(UINT8));
 
   /* Initialize sent_table FALSE so table will be written to JPEG file. */
   (*htblptr)->sent_table = FALSE;