split libandroid.so

- ANativeWindow (native_window.h) and
  AHardwareBuffer (hardware_buffer.h) now live
  in libnativewindow.so, which is a vodka library.

- libandroid.so still provide those symbols
  via a static library version (libnativewindow.a)

- removed libbinder dependency as well

Test: compiled & booted
Bug: 35164655
Change-Id: Ib4bc8e8fc9ec1891bcbee63c28fd0131d82edf29
diff --git a/libs/gui/Android.bp b/libs/gui/Android.bp
index ddf1072..8f9c38a 100644
--- a/libs/gui/Android.bp
+++ b/libs/gui/Android.bp
@@ -107,6 +107,7 @@
         "libGLESv2",
         "libui",
         "libutils",
+        "libnativewindow",
         "liblog",
     ],