Merge PageLoadingPerfTest into ReplayPerfTest
https://bugs.webkit.org/show_bug.cgi?id=111027

Reviewed by Dirk Pranke.

Merged two classes.

We should really move ahead with the bug 100991 and get rid of PageLoadingPerfTest
part of ReplayPerfTest.

* Scripts/webkitpy/performance_tests/perftest.py:
(ReplayPerfTest): Moved _FORCE_GC_FILE here.
(ReplayPerfTest.__init__):
(ReplayPerfTest._run_with_driver): Moved from PageLoadingPerfTest.
(ReplayPerfTest.run_single): Load the GC page as run_single on PageLoadingPerfTest did.
* Scripts/webkitpy/performance_tests/perftest_unittest.py:
(TestReplayPerfTest):
(TestReplayPerfTest.test_run_single.run_test):
(TestReplayPerfTest.test_run_single): Make sure test_time is passed down properly from output.
(TestReplayPerfTest.test_run_with_driver_accumulates_results): Renamed from
TestPageLoadingPerfTest.test_run.
(TestReplayPerfTest.test_run_with_driver_accumulates_results.mock_run_signle):
(TestReplayPerfTest.test_run_with_driver_accumulates_memory_results): Renamed from
TestPageLoadingPerfTest.test_run_with_memory_output
(TestReplayPerfTest.test_run_with_driver_accumulates_memory_results.mock_run_signle):
(TestReplayPerfTest.test_prepare_calls_run_single):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@144255 268f45cc-cd09-0410-ab3c-d52691b4dbfc