Turn Server-Timing experimental feature on

provisioning/configuration/roles/buildbot-worker/tasks/darwin.yml

@@ -43,6 +43,7 @@
   with_items:
     - ../../src/scripts/safari-enable-automation.sh
     - ../../src/scripts/safari-disable-popup-blocker.sh
+    - ../../src/scripts/safari-enable-experimental-features.sh
 
 - name: Allow application user to enable remote automation in Safari
   lineinfile:

src/master/master.cfg

@@ -116,6 +116,10 @@ def render_chunked_builder(properties):
 
     return ['GNU/Linux Chunked Runner']
 
+@util.renderer
+def is_safari(properties):
+    return properties.getProperty('browser_name') == 'safari'
+
 @util.renderer
 def is_local_safari(properties):
     return (properties.getProperty('browser_name') == 'safari' and
@@ -333,6 +337,10 @@ chunked_factory = util.BuildFactory(
                                           util.Property('browser_url')],
                                  haltOnFailure=True,
                                  doStepIf=lambda step: step.build.properties.getProperty('browser_url')),
+    steps.ShellCommand(name='Enable Safari Experimental Features',
+                       command=['safari-enable-experimental-features.sh'],
+                       haltOnFailure=True,
+                       doStepIf=is_safari),
     steps.SetProperty(property='browser_binary',
                       value='/Applications/Safari.app/Contents/MacOS/Safari',
                       doStepIf=is_local_safari_stable,

src/scripts/safari-enable-experimental-features.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+# turn on experimental features
+
+# TODO(cvazac) Remove this if/when Server-Timing is enabled by default in Safari
+defaults write com.apple.Safari ExperimentalServerTimingEnabled -bool true
+
+echo Closing all instances of the application to ensure the changes
+echo are observed.
+
+killall -9 Safari || true