[ChromeDriver] Fix release notes handling

The release script was recently modified to change to a temp dir
as its working directory, and that caused it to look for notes.txt
in the wrong location. This CL fixes it.

Change-Id: Ib0d0abe2689a5bc80c4e6079e5cde2588f5b7a5d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2155202Reviewed-by: Wenbin Zhang <wenbinzhang@google.com>
Commit-Queue: John Chen <johnchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#760366}

chrome/test/chromedriver/support/release/release.sh

@@ -12,6 +12,7 @@ then
   exit 1
 fi
 
+origdir=`pwd`
 workdir=`mktemp -d`
 if [[ -z $workdir ]]
 then
@@ -65,7 +66,7 @@ major=`echo $version | sed 's/\.[0-9.]\+$//'`
 gsutil -h Content-Type:text/plain cp latest gs://chromedriver/LATEST_RELEASE_$build
 gsutil -h Content-Type:text/plain cp latest gs://chromedriver/LATEST_RELEASE_$major
 
-if [[ -f notes.txt ]]
+if [[ -f $origdir/notes.txt ]]
 then
-  gsutil cp notes.txt gs://chromedriver/$version/notes.txt
+  gsutil cp $origdir/notes.txt gs://chromedriver/$version/notes.txt
 fi