[PPAPI] Add browser tests for compositor API

 And fix a bug found with the tests.
 BindGraphics() does not work for a device which is in the same type with the current bound device.

BUG=374383
[email protected], [email protected]

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=278728

Review URL: https://codereview.chromium.org/324983005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@278779 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/ppapi/ppapi_sources.gypi b/ppapi/ppapi_sources.gypi
index 8c0c531..10f2d16 100644
--- a/ppapi/ppapi_sources.gypi
+++ b/ppapi/ppapi_sources.gypi
@@ -406,6 +406,8 @@
       'tests/test_audio_config.h',
       'tests/test_case.cc',
       'tests/test_case.h',
+      'tests/test_compositor.cc',
+      'tests/test_compositor.h',
       'tests/test_console.cc',
       'tests/test_console.h',
       'tests/test_core.cc',