Add icu_assets GN rule

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index 7dacd6b7fa23c16bbf0342d335135a4cafac2b46..77f8aa6a06e90fc4df8f4126f0bb96e2ee33f2bb 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -4,6 +4,10 @@
 
 import("//third_party/icu/config.gni")
 
+if (is_android) {
+  import("//build/config/android/rules.gni")
+}
+
 # Meta target that includes both icuuc and icui18n. Most targets want both.
 # You can depend on the individually if you need to.
 group("icu") {
@@ -521,6 +525,16 @@ component("icuuc") {
   }
 }
 
+if (is_android) {
+  android_assets("icu_assets") {
+    if (icu_use_data_file) {
+      sources = [ "$root_out_dir/icudtl.dat" ]
+      deps = [ ":icudata" ]
+      disable_compression = true
+    }
+  }
+}
+
 # TODO(GYP) support use_system_icu.
 if (icu_use_data_file) {
   if (is_ios) {