Update libjpeg-turbo to v2.0.90 (2.1 beta1)

Update Chromium's copy of libjpeg-turbo to the latest upstream
release (v2.0.90) and re-apply our local changes documented in
README.chromium.

Cherry-pick two additional changes from upstream to fix bugs found
by fuzzers:
1) https://github.com/libjpeg-turbo/libjpeg-turbo/commit/ccaba5d7894ecfb5a8f11e48d3f86e1f14d5a469
2) https://github.com/libjpeg-turbo/libjpeg-turbo/commit/c7ca521bc85b57d41d3ad4963c13fc0100481084

Significant changes provided by this update:
1) A large performance boost to JPEG encoding due to an improved
   Huffman encoding implementation.
2) The complete removal of Arm Neon assembly code. This allows Arm's
   control-flow integrity security features (Armv8.3-A Pointer
   Authentication and Armv8.5-A Branch Target Identification) to be
   switched on with the appropriate compiler flags.

Bug: 922430
Bug: b/135180511
Bug: 919548, 1145581
Change-Id: I319fcdc55b3fd5b219425c07a4e4a03587f4e06d
diff --git a/jctrans.c b/jctrans.c
index ce70a30..ab6a218 100644
--- a/jctrans.c
+++ b/jctrans.c
@@ -4,8 +4,8 @@
  * This file was part of the Independent JPEG Group's software:
  * Copyright (C) 1995-1998, Thomas G. Lane.
  * Modified 2000-2009 by Guido Vollbeding.
- * It was modified by The libjpeg-turbo Project to include only code relevant
- * to libjpeg-turbo.
+ * libjpeg-turbo Modifications:
+ * Copyright (C) 2020, D. R. Commander.
  * For conditions of distribution and use, see the accompanying README.ijg
  * file.
  *
@@ -17,6 +17,7 @@
 #define JPEG_INTERNALS
 #include "jinclude.h"
 #include "jpeglib.h"
+#include "jpegcomp.h"
 
 
 /* Forward declarations */