flashrom: add option for google chromebook fork

src/flashrom/default.nix

@@ -1,34 +1,53 @@
 { stdenv
 , lib
+, fetchgit
 , fetchFromGitHub
 , installShellFiles
 , libftdi1
 , libusb1
 , pciutils
 , pkg-config
+
+# use google's out-of-tree flashrom which can manipulate the
+# write-protection registers of the chromebooks' on-board flash
+# chips
+, forChromebook ? false
 }:
 
 stdenv.mkDerivation {
   pname = "flashrom";
-  version = "1.2+wp";
+  version = if !forChromebook then "1.2+wp" else "0.9.9+d2da98-google";
 
-  src = fetchFromGitHub {
+  src =
+    if !forChromebook
+    then fetchFromGitHub {
       owner = "flashrom";
       repo = "flashrom";
       rev = "cd9b7b427d19e591c1091cb783a51951ef3aeffc";
       sha256 = "sha256-gK/z+WkEHFmT/dYnNLMn4Cb2ESBfqipc19ZVxmaZabQ=";
+    } else fetchgit {
+      url = "https://chromium.googlesource.com/chromiumos/third_party/flashrom";
+      rev = "d2da987986cf2b7f048174ba339907cc760b1c3d";
+      hash = "sha256-nB8B0MXjVpAsg4+0VvO5jqRBsmEHdllgIMkTmaBJ6gE=";
     };
 
   nativeBuildInputs = [ pkg-config installShellFiles ];
   buildInputs = lib.optional (!stdenv.hostPlatform.isStatic) libftdi1
                 ++ [ libusb1 pciutils ];
 
-  patches = [
+  patches =
+    if !forChromebook then [
       ./0001-implement-wp-enable-disable-for-gigadevice-flash-chi.patch
       ./0002-layout.c-allow-nested-regions.patch
+    ] else [
+      ../platform/kevin/chromebook-flashrom-kludges.patch
     ];
 
-  makeFlags = [ "PREFIX=$(out)" "libinstall" ];
+  makeFlags = if !forChromebook then [
+    "PREFIX=$(out)" "libinstall"
+  ] else [
+    "PREFIX=$(out)" "install"
+  ];
 
   meta = with lib; {
     homepage = "https://www.flashrom.org";