GN: wrap libperfetto_android_internal in perfetto_build_with_android

Context: chromium roll breakage http://crrev.com/c/2625893 .
I am not sure this will fix the issue but at very least should
make it more obvious. I still cannot find any GN path that would
include android_internal in chromium builds.
Also fix a trailing /  introduced by aosp/1512303 (I don't think
that's the culprit either)

Change-Id: I3aa258f119a3153c9e239fee6f36d34901e67936
diff --git a/Android.bp b/Android.bp
index 451c339..43d2309 100644
--- a/Android.bp
+++ b/Android.bp
@@ -615,9 +615,13 @@
 cc_library_shared {
   name: "libperfetto_android_internal",
   srcs: [
-    ":perfetto_src_android_internal_android_internal",
     ":perfetto_src_android_internal_headers",
     ":perfetto_src_android_stats_perfetto_atoms",
+    "src/android_internal/atrace_hal.cc",
+    "src/android_internal/health_hal.cc",
+    "src/android_internal/incident_service.cc",
+    "src/android_internal/power_stats_hal.cc",
+    "src/android_internal/statsd_logging.cc",
   ],
   shared_libs: [
     "android.hardware.atrace@1.0",
@@ -6449,18 +6453,6 @@
   ],
 }
 
-// GN: //src/android_internal:android_internal
-filegroup {
-  name: "perfetto_src_android_internal_android_internal",
-  srcs: [
-    "src/android_internal/atrace_hal.cc",
-    "src/android_internal/health_hal.cc",
-    "src/android_internal/incident_service.cc",
-    "src/android_internal/power_stats_hal.cc",
-    "src/android_internal/statsd_logging.cc",
-  ],
-}
-
 // GN: //src/android_internal:headers
 filegroup {
   name: "perfetto_src_android_internal_headers",