Add -fvisibility=default to libchromeos targets

BUG=chromium:315233
TEST=x86-generic-full and daisy-full trybots pass

Change-Id: I15eb018c14758603ccaf8d2e275a74ef4da68f86
Reviewed-on: https://chromium-review.googlesource.com/175750
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Liam McLoughlin <lmcloughlin@chromium.org>
Tested-by: Liam McLoughlin <lmcloughlin@chromium.org>
diff --git a/libchromeos.gypi b/libchromeos.gypi
index 132a7d4..47d89f1 100644
--- a/libchromeos.gypi
+++ b/libchromeos.gypi
@@ -38,6 +38,10 @@
         ],
         'deps': ['<@(exported_deps)'],
       },
+      'cflags': [
+        # TODO: crosbug.com/315233
+        '-fvisibility=default',
+      ],
       'all_dependent_settings': {
         'variables': {
           'deps': [
@@ -67,6 +71,10 @@
         'exported_deps': ['openssl'],
         'deps': ['<@(exported_deps)'],
       },
+      'cflags': [
+        # TODO: crosbug.com/315233
+        '-fvisibility=default',
+      ],
       'all_dependent_settings': {
         'variables': {
           'deps': [
@@ -100,9 +108,6 @@
           ],
         },
       },
-      'cflags': [
-        '-fvisibility=hidden',
-      ],
       'ldflags': [
         '-Wl,--version-script,<(platform_root)/libchromeos/libpolicy.ver',
       ],