Enable SecureSocket on Fuchsia using BoringSSL

runtime/bin/BUILD.gn

Index: runtime/bin/BUILD.gn
diff --git a/runtime/bin/BUILD.gn b/runtime/bin/BUILD.gn
index 56bb53a14922a5f7cb983784f38afb9b551d9591..0e75ba274aacd5a48092d2a03589faefe1628bbd 100644
--- a/runtime/bin/BUILD.gn
+++ b/runtime/bin/BUILD.gn
@@ -7,7 +7,7 @@ import("gypi_contents.gni")
 declare_args() {
   # Whether to fall back to built-in root certificates when they cannot be
   # verified at the operating system level.
-  dart_use_fallback_root_certificates = false
+  dart_use_fallback_root_certificates = true
 
   # The BUILD.gn file that we pull from chromium as part of zlib has a
   # dependence on //base, which we don't pull in. In a standalone build of the
@@ -419,8 +419,6 @@ template("dart_io") {
       if (is_mac) {
         libs += [ "CoreServices.framework" ]
       }
-    } else if (defined(is_fuchsia) && is_fuchsia) {
-      defines += [ "DART_IO_SECURE_SOCKET_DISABLED" ]
     } else {
       deps = [
         "//third_party/boringssl",
@@ -439,7 +437,7 @@ template("dart_io") {
                  "log.h",
                ] + extra_sources
 
-    if (is_linux || is_win) {
+    if (is_linux || is_win || (defined(is_fuchsia) && is_fuchsia)) {
       if (dart_use_fallback_root_certificates) {
         sources += [ "//third_party/root_certificates/root_certificates.cc" ]
       } else {