[Android] Re-write the gtest TestRunner and introduce a new generic sharder.

build/android/pylib/base/new_base_test_runner.py

Index: build/android/pylib/base/new_base_test_runner.py
diff --git a/build/android/pylib/base/base_test_runner.py b/build/android/pylib/base/new_base_test_runner.py
similarity index 93%
copy from build/android/pylib/base/base_test_runner.py
copy to build/android/pylib/base/new_base_test_runner.py
index a4172ddf33eac3d27932d7a48eced92ef10122fb..4e7d3443f6d0f1ef8c9949dbd372c6143adcb559 100644
--- a/build/android/pylib/base/base_test_runner.py
+++ b/build/android/pylib/base/new_base_test_runner.py
@@ -32,7 +32,7 @@ class BaseTestRunner(object):
   the Run() method will set up tests, run them and tear them down.
   """
 
-  def __init__(self, device, tool, shard_index, build_type):
+  def __init__(self, device, tool, build_type):
     """
       Args:
         device: Tests will run on the device of this ID.
@@ -48,7 +48,6 @@ class BaseTestRunner(object):
     self.forwarder_base_url = ('http://localhost:%d' %
         self._forwarder_device_port)
     self.flags = FlagChanger(self.adb)
-    self.shard_index = shard_index
     self.flags.AddFlags(['--disable-fre'])
     self._spawning_server = None
     self._spawner_forwarder = None
@@ -66,17 +65,18 @@ class BaseTestRunner(object):
                              '%d:%d' % (self.test_server_spawner_port,
                                         self.test_server_port))
 
-  def Run(self):
-    """Calls subclass functions to set up tests, run them and tear them down.
+  def Run(self, test):
+    """Calls subclass functions to set up test, run it and tear it down.
+
+    Args:
+      test: A Test to run.
 
     Returns:
-      Test results returned from RunTests().
+      Test results returned from RunTest(test).
     """
-    if not self.HasTests():
-      return True
     self.SetUp()
     try:
-      return self.RunTests()
+      return self.RunTest(test)
     finally:
       self.TearDown()
 
@@ -84,12 +84,8 @@ class BaseTestRunner(object):
     """Called before tests run."""
     Forwarder.KillDevice(self.adb, self.tool)
 
-  def HasTests(self):
-    """Whether the test suite has tests to run."""
-    return True
-
-  def RunTests(self):
-    """Runs the tests. Need to be overridden."""
+  def RunTest(self, test):
+    """Runs the tests. Needs to be overridden."""
     raise NotImplementedError
 
   def TearDown(self):