Build harfbuzz on top of libicu.so

libicu.so is a public library exposed in NDK. Use libicu.so because
it provides enough APIs used by harfbuzz.

It helps deprecate libandroidicu.so and allow i18n module to be
mainline.

Bug: 174051744
Test: m droid
Change-Id: I1b3939520ba31e46d8feeb65785a89e5fe4fb417
diff --git a/Android.bp b/Android.bp
index 9f29062..609f883 100644
--- a/Android.bp
+++ b/Android.bp
@@ -108,16 +108,11 @@
     target: {
         android: {
             shared_libs: [
-                "libandroidicu",
                 "libcutils",
                 "libutils",
             ],
         },
         host: {
-            shared_libs: [
-                "libicui18n",
-                "libicuuc",
-            ],
             static_libs: [
                 "libcutils",
                 "libutils",
@@ -129,6 +124,7 @@
     },
 
     shared_libs: [
+        "libicu",
         "liblog",
     ],