Fix DEPS file patching in push-to-trunk.sh

tools/push-to-trunk.sh

 #!/bin/bash
 # 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
@@ skipping 314 matching lines @@
   let CURRENT_STEP+=1
   if [ $START_STEP -le $CURRENT_STEP ] ; then
     echo ">>> Step $CURRENT_STEP: Switch to Chromium checkout."
     V8_PATH=$(pwd)
     persist "V8_PATH"
     cd "$CHROME_PATH"
     initial_environment_checks
     # Check for a clean workdir.
     [[ -z "$(git status -s -uno)" ]] \
       || die "Workspace is not clean. Please commit or undo your changes."
+    # Assert that the DEPS file is there.
+    [[ -w "DEPS" ]] || die "DEPS file not present or not writable; \
+current directory is: $(pwd)."
   fi
 
   let CURRENT_STEP+=1
   if [ $START_STEP -le $CURRENT_STEP ] ; then
     echo ">>> Step $CURRENT_STEP: Update the checkout and create a new branch."
     git checkout master || die "'git checkout master' failed."
     git pull || die "'git pull' failed, please try again."
     restore_if_unset "TRUNK_REVISION"
     git checkout -b "v8-roll-$TRUNK_REVISION" \
       || die "Failed to checkout a new branch."
   fi
 
   let CURRENT_STEP+=1
   if [ $START_STEP -le $CURRENT_STEP ] ; then
     echo ">>> Step $CURRENT_STEP: Create and upload CL."
     # Patch DEPS file.
-    sed -e "/\"v8_revision\": /s/\"[0-9]+\"/\"$TRUNK_REVISION\"/" \
+    sed -r -e "/\"v8_revision\": /s/\"[0-9]+\"/\"$TRUNK_REVISION\"/" \
         -i DEPS
     restore_version_if_unset
     echo -n "Please enter the email address of a reviewer for the roll CL: "
     read REVIEWER
     git commit -am "Update V8 to version $MAJOR.$MINOR.$BUILD.
 
 TBR=$REVIEWER" || die "'git commit' failed."
     git cl upload --send-mail --use-commit-queue \
       || die "'git cl upload' failed, please try again."
     echo "CL uploaded and sent to commit queue."
@@ skipping 18 matching lines @@
 update the v8rel spreadsheet:"
   else
     echo "Congratulations, you have successfully created the trunk revision \
 $MAJOR.$MINOR.$BUILD. Please don't forget to roll this new version into \
 Chromium, and to update the v8rel spreadsheet:"
   fi
   echo -e "$MAJOR.$MINOR.$BUILD\ttrunk\t$TRUNK_REVISION"
   common_cleanup
   [[ "$TRUNKBRANCH" != "$CURRENT_BRANCH" ]] && git branch -D $TRUNKBRANCH
 fi