Stop removing hide_all_but_jni_onload config from libc++

This is no longer needed and causes gn analyze to fail on Android component
builds since the hide_all_but_jni_onload config is never added.

BUG=846855
R=thakis

Change-Id: I0a9961f6fbda74cd5d3c71a3420588d02bfd86f8
diff --git a/third_party/libc++/BUILD.gn b/third_party/libc++/BUILD.gn
index 6049d72..7e0bebc 100644
--- a/third_party/libc++/BUILD.gn
+++ b/third_party/libc++/BUILD.gn
@@ -69,9 +69,6 @@
     "//build/config/compiler:no_rtti",
     "//build/config/coverage:default_coverage",
   ]
-  if (is_android && is_component_build) {
-    configs -= [ "//build/config/android:hide_all_but_jni_onload" ]
-  }
   configs += [
     ":config",
     "//build/config/compiler:no_chromium_code",