Upgrade libtiff to 4.0.7.

Change-Id: If3f67767f738b7f23230ca8c37c9af2e31696e82
Reviewed-on: https://pdfium-review.googlesource.com/3117
Commit-Queue: dsinclair <dsinclair@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>
diff --git a/third_party/libtiff/tif_packbits.c b/third_party/libtiff/tif_packbits.c
index 9e77190..d2a0165 100644
--- a/third_party/libtiff/tif_packbits.c
+++ b/third_party/libtiff/tif_packbits.c
@@ -1,4 +1,4 @@
-/* $Id: tif_packbits.c,v 1.22 2012-06-20 05:25:33 fwarmerdam Exp $ */
+/* $Id: tif_packbits.c,v 1.24 2016-09-04 21:32:56 erouault Exp $ */
 
 /*
  * Copyright (c) 1988-1997 Sam Leffler
@@ -38,7 +38,8 @@
 {
 	(void) s;
 
-	if (!(tif->tif_data = (uint8*)_TIFFmalloc(sizeof(tmsize_t))))
+        tif->tif_data = (uint8*)_TIFFmalloc(sizeof(tmsize_t));
+	if (tif->tif_data == NULL)
 		return (0);
 	/*
 	 * Calculate the scanline/tile-width size in bytes.
@@ -81,7 +82,9 @@
 		/*
 		 * Find the longest string of identical bytes.
 		 */
-		b = *bp++, cc--, n = 1;
+		b = *bp++;
+		cc--;
+		n = 1;
 		for (; cc > 0 && b == *bp; cc--, bp++)
 			n++;
 	again:
@@ -222,7 +225,8 @@
 	bp = (char*) tif->tif_rawcp;
 	cc = tif->tif_rawcc;
 	while (cc > 0 && occ > 0) {
-		n = (long) *bp++, cc--;
+		n = (long) *bp++;
+		cc--;
 		/*
 		 * Watch out for compilers that
 		 * don't sign extend chars...
@@ -241,7 +245,8 @@
 				n = (long)occ;
 			}
 			occ -= n;
-			b = *bp++, cc--;
+			b = *bp++;
+			cc--;
 			while (n-- > 0)
 				*op++ = (uint8) b;
 		} else {		/* copy next n+1 bytes literally */