Add per-buffer perfetto trace points for SurfaceFlinger frame events

In order to track how buffers move through the system, we add per-buffer perfetto trace points for SurfaceFlinger.
The majority of these were already tracked through TimeStats, so the new tracing was built on top of TimeStats.

Test: atest libsurfaceflinger_unittest

Run trace with:
{ adb shell perfetto   -c - --txt   -o /data/misc/perfetto-traces/trace <<EOF
buffers: {
    size_kb: 1280
}
data_sources: {
    config {
        name: "android.surfaceflinger.timestats"
    }
}
duration_ms: 3000
EOF
} && adb pull /data/misc/perfetto-traces/trace ~/Desktop/trace

Change-Id: Ifb38c64a9966fece735f0ad72438c7c9c5e07baa
diff --git a/services/surfaceflinger/TimeStats/Android.bp b/services/surfaceflinger/TimeStats/Android.bp
new file mode 100644
index 0000000..9e1d503
--- /dev/null
+++ b/services/surfaceflinger/TimeStats/Android.bp
@@ -0,0 +1,15 @@
+cc_library_static {
+    name: "libtimestats",
+    defaults: ["surfaceflinger_defaults"],
+    srcs: [
+      "TimeStats.cpp"
+    ],
+    export_include_dirs: ["."],
+    static_libs: [
+      "libperfetto_client_experimental",
+    ],
+    shared_libs: [
+      "libtimestats_proto",
+      "libui",
+    ],
+}