profiling: Add sampler.

Change-Id: I23e58648423c696648527d277ca6a7ef40a92dca
diff --git a/Android.bp b/Android.bp
index e7f0d6c..b6dadc0 100644
--- a/Android.bp
+++ b/Android.bp
@@ -3850,6 +3850,8 @@
     "src/profiling/memory/heapprofd_integrationtest.cc",
     "src/profiling/memory/record_reader.cc",
     "src/profiling/memory/record_reader_unittest.cc",
+    "src/profiling/memory/sampler.cc",
+    "src/profiling/memory/sampler_unittest.cc",
     "src/profiling/memory/socket_listener.cc",
     "src/profiling/memory/socket_listener_unittest.cc",
     "src/profiling/memory/string_interner.cc",