Increase timeout for grabbing lock

Allow more leeway if machine is under heavy load

BUG=chromium:678677
TEST=None

Change-Id: Id2bd44bea5e3e103e4fbfebd107d0b439330fbdc

create_venv

diff --git a/create_venv b/create_venv
index 7840136..1be6047 100755
--- a/create_venv
+++ b/create_venv
@@ -27,8 +27,8 @@
 
   mkdir -p "$venv_dir"
   (
-    # Try to acquire a lock for 90 seconds.
-    if ! flock -w 90 9; then
+    # Try to acquire a lock for 3 minutes
+    if ! flock -w 180 9; then
       echo 'Failed to acquire lock on virtualenv' >&2
       exit 1
     fi