trace_processor: Fix json tokenizer to handle nested {}

Change-Id: I2b573d3d04e12659ddb6068d308a11dc8674cb2a
diff --git a/src/trace_processor/BUILD.gn b/src/trace_processor/BUILD.gn
index b60f291..dc489f9 100644
--- a/src/trace_processor/BUILD.gn
+++ b/src/trace_processor/BUILD.gn
@@ -235,7 +235,10 @@
     "../protozero",
   ]
   if (perfetto_build_standalone) {
-    sources += [ "json_trace_utils_unittest.cc" ]
+    sources += [
+      "json_trace_tokenizer_unittest.cc",
+      "json_trace_utils_unittest.cc",
+    ]
     deps += [ "../../gn:jsoncpp_deps" ]
   }
 }