Convert media effects to Android.bp

See build/soong/README.md for more information.

Also removed some obsolete subdirs entries.

Test: m MODULES-IN-frameworks-av-media-libeffects
Change-Id: I1111197a62cc0e856159bfa0d650c5c36b20890a
diff --git a/media/libeffects/preprocessing/Android.bp b/media/libeffects/preprocessing/Android.bp
new file mode 100644
index 0000000..c87635f
--- /dev/null
+++ b/media/libeffects/preprocessing/Android.bp
@@ -0,0 +1,35 @@
+// audio preprocessing wrapper
+cc_library_shared {
+    name: "libaudiopreprocessing",
+
+    vendor: true,
+
+    relative_install_path: "soundfx",
+
+    srcs: ["PreProcessing.cpp"],
+
+    include_dirs: [
+        "external/webrtc",
+        "external/webrtc/webrtc/modules/include",
+        "external/webrtc/webrtc/modules/audio_processing/include",
+    ],
+
+    shared_libs: [
+        "libwebrtc_audio_preprocessing",
+        "libspeexresampler",
+        "libutils",
+        "liblog",
+    ],
+
+    cflags: [
+        "-DWEBRTC_POSIX",
+        "-fvisibility=hidden",
+        "-Wall",
+        "-Werror",
+    ],
+
+    header_libs: [
+        "libaudioeffects",
+        "libhardware_headers",
+    ],
+}