Add GN build targets for the rest of mojo/public

build/config/android/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/android/config.gni")
 import("//build/config/sysroot.gni")
 
 config("sdk") {
   if (sysroot != "") {
     cflags = [ "--sysroot=" + sysroot ]
     ldflags = [ "--sysroot=" + sysroot ]
 
     # Need to get some linker flags out of the sysroot.
     sysroot_ld_path = rebase_path("//build/config/linux/sysroot_ld_path.py")
     ldflags += [ exec_script(sysroot_ld_path,
         [ rebase_path("//build/linux/sysroot_ld_path.sh"), sysroot ],
         "value")
     ]
   }
 }
+
+# Don't export symbols from statically linked libraries.
+config("no_export_static_lib_symbols") {
+  ldflags = [ "-Wl,--exclude-libs=ALL" ]
+}