Refactor the way that TestApi works so that it is actually useful.

scripts/slave/recipe_modules/properties/test_api.py

+from slave import recipe_test_api
+
+class PropertiesTestApi(recipe_test_api.RecipeTestApi):
+  def generic(self, **kwargs):
+    """
+    Merge kwargs into a typical buildbot properties blob, and return the blob.
+    """
+    ret = self.Properties(
+        blamelist='cool_dev1337@chromium.org,hax@chromium.org',
+        blamelist_real=['cool_dev1337@chromium.org', 'hax@chromium.org'],
+        buildername='TestBuilder',
+        buildnumber=571,
+        mastername='chromium.testing.master',
+        slavename='TestSlavename',
+        workdir='/path/to/workdir/TestSlavename',
+    )
+    ret.properties.update(kwargs)
+    return ret
+
+  def scheduled(self, **kwargs):
+    """
+    Merge kwargs into a typical buildbot properties blob for a job fired off
+    by a chrome/trunk svn scheduler, and return the blob.
+    """
+    ret = self.generic(
+        branch='TestBranch',
+        project='',
+        repository='svn://svn-mirror.golo.chromium.org/chrome/trunk',
+        revision='204787',
+    )
+    ret.properties.update(kwargs)
+    return ret
+
+  def tryserver(self, **kwargs):
+    """
+    Merge kwargs into a typical buildbot properties blob for a job fired off
+    by a rietveld tryjob on the tryserver, and return the blob.
+    """
+    ret = self.generic(
+        branch='',
+        issue=12853011,
+        patchset=1,
+        project='chrome',
+        repository='',
+        requester='commit-bot@chromium.org',
+        revision='HEAD',
+        rietveld='https://chromiumcodereview.appspot.com',
+        root='src',
+    )
+    ret.properties.update(kwargs)
+    return ret