Fix support for app package name.

The app package name was not being reported to the media stats. This
change adds the package name as part of the report to media stats.

This is one of two parts to this change. The other part is in
frameworks/av.

Bug: 64584568

Test: Unit tests, GTS tests, tried with Google Play Movies.
Change-Id: I1ca09db3a59d9a0950f424d977f8774dffd09c2b

libwvdrmengine/cdm/test/wv_cdm_metrics_test.cpp

@@ -106,7 +106,7 @@ TEST_F(WvContentDecryptionModuleMetricsTest, EngineAndSessionMetrics) {
 TEST_F(WvContentDecryptionModuleMetricsTest, MultipleEngineMetric) {
   CdmSessionId session_id;
   wvcdm::CdmKeySystem key_system("com.widevine");
-  CdmIdentifier identifier = { "foo", "bar" };
+  CdmIdentifier identifier = { "foo", "bar", "baz" };
 
   // Openning the session will fail with NEEDS_PROVISIONING error. But it will
   // still create some session-level stats.
@@ -146,6 +146,9 @@ TEST_F(WvContentDecryptionModuleMetricsTest, MultipleEngineMetric) {
         metrics.metric_sub_group(i).metric_sub_group(0).metric(0).name(),
         StrEq("/drm/widevine/cdm_session/session_id"));
   }
+
+  // Verify that the second metrics app package name is set.
+  EXPECT_THAT(metrics.metric_sub_group(1).app_package_name(), StrEq("baz"));
 }
 
 }