Expose status, add backward compat in tests and remove unused code

* Expose release and offline statuses in CdmEngine.

  [ Merge of http://go/wvgerrit/14616 ]

  This will allow me to make some intelligent decisions in the new CE
  CDM implementation without having to duplicate all the information
  known in the lower levels.

* Account for backward compat support in tests

  [ Merge of http://go/wvgerrit/14621 ]

  One test ensures that device path backward compatibility is working,
  while another assumes it is used.

  This fixes test results when
  Properties::security_level_path_backward_compatibility_support()
  is false.

  Previously, the CE CDM did not run these tests, and so this went
  unnoticed.

* Remove Lock::Try, which is not used.

  [ Merge of http://go/wvgerrit/14624 ]

Change-Id: Id18cf1f5b18c7322b8b636819276361af225734f

libwvdrmengine/cdm/core/test/device_files_unittest.cpp

@@ -1634,7 +1634,9 @@ TEST_P(DeviceCertificateTest, ReadCertificate) {
                       Return(data.size())));
   EXPECT_CALL(file, Close()).Times(1);
   EXPECT_CALL(file, Write(_, _)).Times(0);
-  EXPECT_CALL(file, List(_, NotNull())).WillOnce(Return(false));
+  if (Properties::security_level_path_backward_compatibility_support()) {
+    EXPECT_CALL(file, List(_, NotNull())).WillOnce(Return(false));
+  }
 
   DeviceFiles device_files;
   EXPECT_TRUE(device_files.Init(kSecurityLevelL1));
@@ -1926,6 +1928,10 @@ TEST_F(DeviceFilesTest, AppParametersBackwardCompatibility) {
 }
 
 TEST_F(DeviceFilesTest, SecurityLevelPathBackwardCompatibility) {
+  if (!Properties::security_level_path_backward_compatibility_support()) {
+    return;
+  }
+
   MockFile file;
   std::vector<std::string> security_dirs;
   EXPECT_TRUE(Properties::GetSecurityLevelDirectories(&security_dirs));