Add quotes around paths in bash scripts.

This allows git-cl to run successfully when the depot tools are installed to a path with a space in it.

Change-Id: I79fa44d13f89fb0ee1baaa90961b4c4284913c40
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2125626
Auto-Submit: John Stiles <johnstiles@google.com>
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>
diff --git a/bootstrap_python3 b/bootstrap_python3
index 02c63d9..96110de 100644
--- a/bootstrap_python3
+++ b/bootstrap_python3
@@ -3,7 +3,7 @@
 function bootstrap_python3 {
   base_dir=$(dirname "${BASH_SOURCE[0]}")
 
-  cd $base_dir
+  cd "${base_dir}"
 
   if [ -e ".bleeding_edge" ]; then
     CIPD_MANIFEST="bootstrap/manifest_bleeding_edge.txt"
@@ -29,7 +29,7 @@
       -root "$BOOTSTRAP_PATH"
 
   BOOTSTRAP_PYTHON_BIN="${BOOTSTRAP_PATH}/python3/bin/python3"
-  "$BOOTSTRAP_PYTHON_BIN" "bootstrap/bootstrap.py" --bootstrap-name $BOOTSTRAP_PATH
+  "$BOOTSTRAP_PYTHON_BIN" "bootstrap/bootstrap.py" --bootstrap-name "$BOOTSTRAP_PATH"
 
   cd - > /dev/null
 }