Always build static lib if not on Fuchsia

This allows us to use Fuchsia's ICU for Flutter.

Change-Id: Ie93e2240ef000f5200f4ed88c23491a05b76d36d
diff --git a/BUILD.gn b/BUILD.gn
index af6c8e4..42c0ef5 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -104,13 +104,7 @@
   }
 }
 
-if (current_toolchain == host_toolchain) {
-  library_type = "static_library"
-} else {
-  library_type = "shared_library"
-}
-
-target(library_type, "icui18n") {
+target(default_library_type, "icui18n") {
   # find  source/i18n -maxdepth 1  ! -type d  | egrep  '\.(c|cpp|h)$' |\
   # sort | sed 's/^\(.*\)$/    "\1",/'
   sources = [
@@ -550,7 +544,7 @@
   public_configs = [ ":icu_config" ]
 }
 
-target(library_type, "icuuc") {
+target(default_library_type, "icuuc") {
   # find  source/common -maxdepth 1  ! -type d  | egrep  '\.(c|cpp|h)$' |\
   # sort | sed 's/^\(.*\)$/    "\1",/'
   sources = [