Allow perfetto to work on iOS

Bug: chromium:1411704
Change-Id: Idc448166625222bc814e71d5db03ae5d302ea394
diff --git a/BUILD.gn b/BUILD.gn
index 0ad78da..bac6cfc 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -297,7 +297,7 @@
       ]
       public_deps += [ "include/perfetto/ext/tracing/ipc:ipc" ]
     }
-    if (!is_nacl && !is_ios) {
+    if (!is_nacl) {
       deps += [
         "src/trace_processor:export_json",
         "src/trace_processor:storage_minimal",