metricsd: Use product id instead of build target id.

We decided to change the name of this identifier to "product id", the
system property where it is stored will also be named
ro.product.product_id.

BUG: 24302729

Change-Id: I0d2f0867b364de98367f0072d216acec76401c33
diff --git a/constants.h b/constants.h
index 717e5d2..8a00fc4 100644
--- a/constants.h
+++ b/constants.h
@@ -28,7 +28,7 @@
 static const char kDefaultVersion[] = "0.0.0.0";
 
 // System properties used.
-static const char kBuildTargetIdProperty[] = "ro.product.build_target_id";
+static const char kProductIdProperty[] = "ro.product.product_id";
 static const char kChannelProperty[] = "ro.product.channel";
 static const char kProductVersionProperty[] = "ro.product.version";
 }  // namespace metrics
diff --git a/uploader/system_profile_cache.cc b/uploader/system_profile_cache.cc
index e3f6339..2437b56 100644
--- a/uploader/system_profile_cache.cc
+++ b/uploader/system_profile_cache.cc
@@ -73,10 +73,10 @@
   CHECK(!initialized_)
       << "this should be called only once in the metrics_daemon lifetime.";
 
-  profile_.build_target_id = GetProperty(metrics::kBuildTargetIdProperty);
+  profile_.product_id = GetProperty(metrics::kProductIdProperty);
 
-  if (profile_.build_target_id.empty()) {
-    LOG(ERROR) << "System property " << metrics::kBuildTargetIdProperty
+  if (profile_.product_id.empty()) {
+    LOG(ERROR) << "System property " << metrics::kProductIdProperty
                << " is not set.";
     return false;
   }
@@ -136,7 +136,7 @@
   profile_proto->set_channel(profile_.channel);
   metrics::SystemProfileProto_BrilloDeviceData* device_data =
       profile_proto->mutable_brillo();
-  device_data->set_build_target_id(profile_.build_target_id);
+  device_data->set_build_target_id(profile_.product_id);
 
   return true;
 }
diff --git a/uploader/system_profile_cache.h b/uploader/system_profile_cache.h
index 1d22fa1..3410157 100644
--- a/uploader/system_profile_cache.h
+++ b/uploader/system_profile_cache.h
@@ -39,7 +39,7 @@
   std::string client_id;
   int session_id;
   metrics::SystemProfileProto::Channel channel;
-  std::string build_target_id;
+  std::string product_id;
 };
 
 // Retrieves general system informations needed by the protobuf for context and
diff --git a/uploader/upload_service_test.cc b/uploader/upload_service_test.cc
index 09748db..0dd7db6 100644
--- a/uploader/upload_service_test.cc
+++ b/uploader/upload_service_test.cc
@@ -224,7 +224,7 @@
   upload_service_->sender_.reset(sender);
 
   SetTestingProperty(metrics::kChannelProperty, "beta");
-  SetTestingProperty(metrics::kBuildTargetIdProperty, "hello");
+  SetTestingProperty(metrics::kProductIdProperty, "hello");
   SetTestingProperty(metrics::kProductVersionProperty, "1.2.3.4");
 
   scoped_ptr<metrics::MetricSample> histogram =
@@ -267,7 +267,7 @@
 }
 
 TEST_F(UploadServiceTest, SessionIdIncrementedAtInitialization) {
-  SetTestingProperty(metrics::kBuildTargetIdProperty, "hello");
+  SetTestingProperty(metrics::kProductIdProperty, "hello");
   SystemProfileCache cache(true, dir_.path());
   cache.Initialize();
   int session_id = cache.profile_.session_id;