Support reverse patching in merge-to-branch.sh

tools/common-includes.sh

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 157 matching lines @@
   unset ANSWER
   while [ "$ANSWER" != "LGTM" ] ; do
     [[ -n "$ANSWER" ]] && echo "That was not 'LGTM'."
     echo -n "> "
     read ANSWER
   done
 }
 
 # Takes a file containing the patch to apply as first argument.
 apply_patch() {
-  patch -p1 < "$1" > "$PATCH_OUTPUT_FILE" || \
+  patch $REVERSE_PATCH -p1 < "$1" > "$PATCH_OUTPUT_FILE" || \
     { cat "$PATCH_OUTPUT_FILE" && die "Applying the patch failed."; }
   tee < "$PATCH_OUTPUT_FILE" >(awk '{print $NF}' >> "$TOUCHED_FILES_FILE")
   rm "$PATCH_OUTPUT_FILE"
 }
 
 stage_files() {
   # Stage added and modified files.
   TOUCHED_FILES=$(cat "$TOUCHED_FILES_FILE")
   for FILE in $TOUCHED_FILES ; do
     git add "$FILE"
   done
   # Stage deleted files.
   DELETED_FILES=$(git status -s -uno --porcelain | grep "^ D" \
                                                  | awk '{print $NF}')
   for FILE in $DELETED_FILES ; do
     git rm "$FILE"
   done
   rm -f "$TOUCHED_FILES_FILE"
 }