Use the new shim libicu available for NDK

The plan is to migrate most users from libandroidicu,
and libandroidicu will be deprecated.

Test: m libpdfium
Change-Id: I72d863e6d2ee05b9780f8ce34181a91586eb82c0
diff --git a/Android.bp b/Android.bp
index 10a2cc3..ed6396a 100644
--- a/Android.bp
+++ b/Android.bp
@@ -96,9 +96,9 @@
 
     // TODO: figure out why turning on exceptions requires manually linking libdl
     shared_libs: [
-        "libandroidicu",
         "libdl",
         "libft2",
+        "libicu",
         "libjpeg",
         "libz",
     ],