chromiumDev: Revert a patch to fix the build with LLVM 12

The build was failing with:
clang++: error: unknown argument: '-fsanitize-ignorelist=../../tools/cfi/ignores.txt'

pkgs/applications/networking/browsers/chromium/common.nix

@@ -54,9 +54,9 @@ let
   # source tree.
   extraAttrs = buildFun base;
 
-  githubPatch = commit: sha256: fetchpatch {
+  githubPatch = { commit, sha256, revert ? false }: fetchpatch {
     url = "https://github.com/chromium/chromium/commit/${commit}.patch";
-    inherit sha256;
+    inherit sha256 revert;
   };
 
   mkGnFlags =
@@ -166,6 +166,14 @@ let
       # Fix the build by adding a missing dependency (s. https://crbug.com/1197837):
       ./patches/fix-missing-atspi2-dependency.patch
       ./patches/closure_compiler-Use-the-Java-binary-from-the-system.patch
+    ] ++ lib.optionals (chromiumVersionAtLeast "93") [
+      # We need to revert this patch to build M93 with LLVM 12.
+      (githubPatch {
+        # Reland "Replace 'blacklist' with 'ignorelist' in ./tools/msan/."
+        commit = "9d080c0934b848ee4a05013c78641e612fcc1e03";
+        sha256 = "1bxdhxmiy6h4acq26lq43x2mxx6rawmfmlgsh5j7w8kyhkw5af0c";
+        revert = true;
+      })
     ];
 
     postPatch = ''