Perfetto Client API (4): Add initial integration test

Adds an initial integration test that coverse the basic case of
of an in-process data source and one session.
More will come in next CLs.

Bug: 132678367
Test: perfetto_integrationtest
Change-Id: I07e774e67c7842d78073e33c87dc658cd06d4616
diff --git a/Android.bp b/Android.bp
index e304cdf..10aad32 100644
--- a/Android.bp
+++ b/Android.bp
@@ -621,7 +621,16 @@
     "src/protozero/scattered_heap_buffer.cc",
     "src/protozero/scattered_stream_null_delegate.cc",
     "src/protozero/scattered_stream_writer.cc",
+    "src/public/api_integrationtest.cc",
+    "src/public/data_source.cc",
+    "src/public/internal/in_process_tracing_backend.cc",
+    "src/public/internal/system_tracing_backend.cc",
+    "src/public/internal/tracing_muxer_impl.cc",
+    "src/public/platform.cc",
+    "src/public/platform_posix.cc",
     "src/public/trace_writer_base.cc",
+    "src/public/tracing.cc",
+    "src/public/virtual_destructors.cc",
     "src/traced/probes/android_log/android_log_data_source.cc",
     "src/traced/probes/filesystem/file_scanner.cc",
     "src/traced/probes/filesystem/fs_mount.cc",