build: only pipe to codecov if tests run on Node 10

.kokoro/lint.sh

@@ -23,9 +23,11 @@ cd $(dirname $0)/..
 npm install
 
 # Install and link samples
-cd samples/
-npm link ../
-npm install
-cd ..
+if [ -f samples/package.json ]; then
+  cd samples/
+  npm link ../
+  npm install
+  cd ..
+fi
 
 npm run lint

.kokoro/samples-test.sh

@@ -31,12 +31,14 @@ if [ -f .kokoro/pre-samples-test.sh ]; then
     set -x
 fi
 
-npm install
+if [ -f samples/package.json ]; then
+    npm install
 
-# Install and link samples
-cd samples/
-npm link ../
-npm install
-cd ..
+    # Install and link samples
+    cd samples/
+    npm link ../
+    npm install
+    cd ..
 
-npm run samples-test
+    npm run samples-test
+fi

.kokoro/test.sh

@@ -22,6 +22,14 @@ cd $(dirname $0)/..
 
 npm install
 npm test
-./node_modules/nyc/bin/nyc.js report
 
-bash $KOKORO_GFILE_DIR/codecov.sh
+COVERAGE_NODE=10
+if npx check-node-version@3.3.0 --silent --node $COVERAGE_NODE; then
+  NYC_BIN=./node_modules/nyc/bin/nyc.js
+  if [ -f "$NYC_BIN" ]; then
+    $NYC_BIN report
+  fi
+  bash $KOKORO_GFILE_DIR/codecov.sh
+else
+  echo "coverage is only reported for Node $COVERAGE_NODE"
+fi

synth.metadata

@@ -1,11 +1,11 @@
 {
-  "updateTime": "2019-04-02T18:07:08.916064Z",
+  "updateTime": "2019-05-04T11:22:40.672305Z",
   "sources": [
     {
       "template": {
         "name": "node_library",
         "origin": "synthtool.gcp",
-        "version": "2019.2.26"
+        "version": "2019.5.2"
       }
     }
   ]