Enable more cc unit tests for LayerTreeHostRemote test.

We have added test classes for LayerTreeHostRemote for Blimp and would
like to reuse cc unit tests to test the following flow:

Engine cc ==> Client cc main thread ==> Client cc impl thread.

This CL goes through about 50 unit test cases in
layer_tree_host_unittest.cc.

BUG=653371
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel

Review-Url: https://codereview.chromium.org/2456093003
Cr-Commit-Position: refs/heads/master@{#429396}

diff --git a/cc/BUILD.gn b/cc/BUILD.gn
index bd968591..48bacc2 100644
--- a/cc/BUILD.gn
+++ b/cc/BUILD.gn

@@ -730,6 +730,10 @@
     "test/pixel_test_output_surface.h",
     "test/pixel_test_utils.cc",
     "test/pixel_test_utils.h",
+    "test/push_properties_counting_layer.cc",
+    "test/push_properties_counting_layer.h",
+    "test/push_properties_counting_layer_impl.cc",
+    "test/push_properties_counting_layer_impl.h",
     "test/remote_client_layer_factory.cc",
     "test/remote_client_layer_factory.h",
     "test/remote_proto_channel_bridge.cc",