test: split integration tests in dedicated files

No functional change. This simply splits the existing
integration tests into dedicated files, to make the
scope of each integration test more clear.
Also doing some minor cleanups:
 - Remove -DPERFETTO_START_DAEMONS_FOR_TESTING as it's
   unused after the introduction of perfetto_build_flags.h
 - Make android-os specific test ifdefed for OS_ANDROID
 - Make ftrace-specific test ifedef for OS_LINUX|OS_ANDROID
 - Soft-enable ftrace tests on Linux, but accept that tracefs
   might not be accessible and skip them in that case.

Bug: 215221322
Change-Id: Ie8288b5b574aaaabf1412da2766c77b91166dc79
diff --git a/Android.bp b/Android.bp
index 1fad0af..19a10f2 100644
--- a/Android.bp
+++ b/Android.bp
@@ -1111,7 +1111,7 @@
         ":perfetto_src_tracing_ipc_default_socket",
         ":perfetto_src_tracing_ipc_producer_producer",
         ":perfetto_src_tracing_ipc_service_service",
-        ":perfetto_test_end_to_end_integrationtests",
+        ":perfetto_test_integrationtests",
         ":perfetto_test_test_helper",
         "test/cts/device_feature_test_cts.cc",
         "test/cts/end_to_end_integrationtest_cts.cc",
@@ -1814,7 +1814,7 @@
         ":perfetto_src_tracing_system_backend",
         ":perfetto_src_tracing_test_api_test_support",
         ":perfetto_src_tracing_test_client_api_integrationtests",
-        ":perfetto_test_end_to_end_integrationtests",
+        ":perfetto_test_integrationtests",
         ":perfetto_test_test_helper",
     ],
     shared_libs: [
@@ -9072,11 +9072,14 @@
     ],
 }
 
-// GN: //test:end_to_end_integrationtests
+// GN: //test:integrationtests
 filegroup {
-    name: "perfetto_test_end_to_end_integrationtests",
+    name: "perfetto_test_integrationtests",
     srcs: [
-        "test/end_to_end_integrationtest.cc",
+        "test/android_integrationtest.cc",
+        "test/cmdline_integrationtest.cc",
+        "test/ftrace_integrationtest.cc",
+        "test/traced_integrationtest.cc",
     ],
 }