Bug 1550075 - Add android user profile to raptor, enable smart disk cache sizing r=rwood

A new user profile, raptor-android, was added. This profile is merged with existing profiles in RaptorAndroid.
browser.cache.disk.smart_size.enabled was enabled in test since it is enabled in shipped apps.
See https://searchfox.org/mozilla-central/rev/11cfa0462a6b5d8c5e2111b8cfddcf78098f0141/mobile/android/app/mobile.js#74

Differential Revision: https://phabricator.services.mozilla.com/D31336

--HG--
extra : moz-landing-system : lando

testing/profiles/raptor-android/extensions/README.txt

@@ -0,0 +1,2 @@
+Dropping extensions here will get them installed in all test harnesses
+that make use of this profile.

testing/profiles/raptor-android/user.js

@@ -0,0 +1,5 @@
+// Preferences file used by the raptor harness exclusively on android
+/* globals user_pref */
+
+// disk cache smart size is enabled in shipped apps
+user_pref("browser.cache.disk.smart_size.enabled", true);

testing/raptor/raptor/raptor.py

@@ -851,6 +851,14 @@ class RaptorAndroid(Raptor):
         for key, value in commands.items():
             self._set_value_and_check_exitcode(key, value, root=True)
 
+    def build_browser_profile(self):
+        super(RaptorAndroid, self).build_browser_profile()
+
+        # Merge in the android profile
+        path = os.path.join(self.profile_data_dir, 'raptor-android')
+        self.log.info("Merging profile: {}".format(path))
+        self.profile.merge(path)
+
     def clear_app_data(self):
         self.log.info("clearing %s app data" % self.config['binary'])
         self.device.shell("pm clear %s" % self.config['binary'])