Make it possible to build cronet without icu.

components/cronet/android/cronet_jni.cc

Index: components/cronet/android/cronet_jni.cc
diff --git a/components/cronet/android/cronet_jni.cc b/components/cronet/android/cronet_jni.cc
index 6a370a3ef0fda8694b9baf22027ca5a15cfca749..f67425bc95654489d8a12ce7ee89a83f1278410d 100644
--- a/components/cronet/android/cronet_jni.cc
+++ b/components/cronet/android/cronet_jni.cc
@@ -6,12 +6,15 @@
 #include "base/android/jni_android.h"
 #include "base/android/jni_registrar.h"
 #include "base/at_exit.h"
-#include "base/i18n/icu_util.h"
 #include "components/cronet/android/org_chromium_net_UrlRequest.h"
 #include "components/cronet/android/org_chromium_net_UrlRequestContext.h"
 #include "net/android/net_jni_registrar.h"
 #include "url/android/url_jni_registrar.h"
 
+#if !defined(USE_ICU_ALTERNATIVES_ON_ANDROID)
+#include "base/i18n/icu_util.h"
+#endif
+
 namespace {
 
 const base::android::RegistrationMethod kCronetRegisteredMethods[] = {
@@ -42,7 +45,9 @@ extern "C" jint JNI_OnLoad(JavaVM* vm, void* reserved) {
 
   g_at_exit_manager = new base::AtExitManager();
 
+#if !defined(USE_ICU_ALTERNATIVES_ON_ANDROID)
   base::i18n::InitializeICU();
+#endif
 
   return JNI_VERSION_1_6;
 }