Pass the binary path of Chrome to wpt run in CI

ChromeDriver doesn't honor PATH and uses /opt/google/chrome/chrome by
default (which is usually the stable channel), so we need to explicitly
pass the desired binary path to wpt run (which in turn passes to
chromedriver via capabilities) in Travis CI (both stability check and
infrastructure test).

tools/ci/ci_stability.sh

@@ -8,15 +8,18 @@ cd $WPT_ROOT
 source tools/ci/lib.sh
 
 test_stability() {
-    ./wpt check-stability $PRODUCT --output-bytes $((1024 * 1024 * 3)) --metadata ~/meta/ --install-fonts
+    local binary_arg=$1
+    ./wpt check-stability $PRODUCT $binary_arg --output-bytes $((1024 * 1024 * 3)) --metadata ~/meta/ --install-fonts
 }
 
 main() {
     hosts_fixup
+    local binary_arg=""
     if [ $(echo $PRODUCT | grep '^chrome:') ]; then
-       install_chrome $(echo $PRODUCT | grep --only-matching '\w\+$')
+       local channel=$(echo $PRODUCT | grep --only-matching '\w\+$')
+       binary_arg="--binary=$(install_chrome $channel)"
     fi
-    test_stability
+    test_stability $binary_arg
 }
 
 main

tools/ci/ci_wptrunner_infrastructure.sh

@@ -11,22 +11,25 @@ test_infrastructure() {
     local ARGS="";
     if [ $PRODUCT == "firefox" ]; then
         ARGS="--install-browser"
+    else
+        ARGS="--binary=$1"
     fi
     ./wpt run --yes --manifest ~/meta/MANIFEST.json --metadata infrastructure/metadata/ --install-fonts $ARGS $PRODUCT infrastructure/
 }
 
 main() {
-    PRODUCTS=( "firefox" )
+    PRODUCTS=( "firefox" "chrome" )
     for PRODUCT in "${PRODUCTS[@]}"; do
         if [ "$PRODUCT" != "firefox" ]; then
             # Firefox is expected to work using pref settings for DNS
             # Don't adjust the hostnames in that case to ensure this keeps working
             hosts_fixup
         fi
         if [ "$PRODUCT" == "chrome" ]; then
-            install_chrome dev
+            test_infrastructure $(install_chrome dev)
+        else
+            test_infrastructure
         fi
-        test_infrastructure
     done
 }
 

tools/ci/lib.sh

@@ -38,4 +38,6 @@ install_chrome() {
       sudo apt-get install --fix-broken
       sudo dpkg --install $deb_archive
     fi
+
+    echo $(which google-chrome-$channel)
 }