merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 43 insertions, 0 deletions

diff --git a/third_party/git/t/t4211/sha1/expect.beginning-of-file b/third_party/git/t/t4211/sha1/expect.beginning-of-file
new file mode 100644
index 0000000000..91b4054898
--- /dev/null
+++ b/third_party/git/t/t4211/sha1/expect.beginning-of-file
@@ -0,0 +1,43 @@
+commit 4a23ae5c98d59a58c6da036156959f2dc9f472ad
+Author: Thomas Rast <trast@student.ethz.ch>
+Date:   Thu Feb 28 10:47:40 2013 +0100
+
+    change at very beginning
+
+diff --git a/a.c b/a.c
+--- a/a.c
++++ b/a.c
+@@ -1,3 +1,4 @@
++#include <unistd.h>
+ #include <stdio.h>
+ 
+ long f(long x)
+
+commit a6eb82647d5d67f893da442f8f9375fd89a3b1e2
+Author: Thomas Rast <trast@student.ethz.ch>
+Date:   Thu Feb 28 10:45:16 2013 +0100
+
+    touch both functions
+
+diff --git a/a.c b/a.c
+--- a/a.c
++++ b/a.c
+@@ -1,3 +1,3 @@
+ #include <stdio.h>
+ 
+-int f(int x)
++long f(long x)
+
+commit de4c48ae814792c02a49c4c3c0c757ae69c55f6a
+Author: Thomas Rast <trast@student.ethz.ch>
+Date:   Thu Feb 28 10:44:48 2013 +0100
+
+    initial
+
+diff --git a/a.c b/a.c
+--- /dev/null
++++ b/a.c
+@@ -0,0 +1,3 @@
++#include <stdio.h>
++
++int f(int x)