vet.sh: don't check git status when doing -install (#1641)

diff --git a/vet.sh b/vet.sh
index 72ef329..cf2db36 100755
--- a/vet.sh
+++ b/vet.sh
@@ -8,12 +8,6 @@
   exit 1
 }
 
-# TODO: Remove this check and the mangling below once "context" is imported
-# directly.
-if git status --porcelain | read; then
-  die "Uncommitted or untracked files found; commit changes first"
-fi
-
 PATH="$GOPATH/bin:$GOROOT/bin:$PATH"
 
 # Check proto in manual runs or cron runs.
@@ -48,6 +42,12 @@
   die "Unknown argument(s): $*"
 fi
 
+# TODO: Remove this check and the mangling below once "context" is imported
+# directly.
+if git status --porcelain | read; then
+  die "Uncommitted or untracked files found; commit changes first"
+fi
+
 git ls-files "*.go" | xargs grep -L "\(Copyright [0-9]\{4,\} gRPC authors\)\|DO NOT EDIT" 2>&1 | tee /dev/stderr | (! read)
 gofmt -s -d -l . 2>&1 | tee /dev/stderr | (! read)
 goimports -l . 2>&1 | tee /dev/stderr | (! read)