Implement the android metrics reporter

Implement the metrics_reporter_android class which reports with
libmetricslogger. We reports the error_code only for now, and more
android metrics will be reported in the following up cls.

Test: mma
Change-Id: Id5760aaa4853fa9ee0248344fa12900b923dfb7f
diff --git a/Android.mk b/Android.mk
index d34898a..8807666 100644
--- a/Android.mk
+++ b/Android.mk
@@ -356,6 +356,7 @@
     libbrillo-binder \
     libcutils \
     libcurl \
+    libmetricslogger \
     libssl \
     libutils
 
@@ -389,6 +390,8 @@
     daemon_state_android.cc \
     hardware_android.cc \
     libcurl_http_fetcher.cc \
+    metrics_reporter_android.cc \
+    metrics_utils.cc \
     network_selector_android.cc \
     proxy_resolver.cc \
     update_attempter_android.cc \
@@ -463,6 +466,8 @@
 LOCAL_SRC_FILES := \
     boot_control_recovery.cc \
     hardware_android.cc \
+    metrics_reporter_android.cc \
+    metrics_utils.cc \
     network_selector_stub.cc \
     proxy_resolver.cc \
     sideload_main.cc \