libmetricslogger: Refactor Tron metrics histogram logging out of
bootstat.

To be shared with other native components that want to log histograms.

Bug: 34456830
Test: libmetricslogger_test
Change-Id: I94a1a91c6d33e443d66bc480158dc2470d6c9031
diff --git a/bootstat/Android.bp b/bootstat/Android.bp
index d98a9d7..f744ad1 100644
--- a/bootstat/Android.bp
+++ b/bootstat/Android.bp
@@ -16,7 +16,6 @@
 
 bootstat_lib_src_files = [
     "boot_event_record_store.cpp",
-    "histogram_logger.cpp",
     "uptime_parser.cpp",
 ]
 
@@ -27,15 +26,12 @@
         "-Wall",
         "-Wextra",
         "-Werror",
-
-        // 524291 corresponds to sysui_histogram, from
-        // frameworks/base/core/java/com/android/internal/logging/EventLogTags.logtags
-        "-DHISTOGRAM_LOG_TAG=524291",
     ],
     shared_libs: [
         "libbase",
         "libcutils",
         "liblog",
+        "libmetricslogger",
     ],
     whole_static_libs: ["libgtest_prod"],
     // Clang is required because of C++14