Fix build (forgot to update BUILD.gn)

TBR=yangguo@chromium.org

Review URL: https://codereview.chromium.org/341063008

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22100 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUILD.gn

@@ -678,6 +678,8 @@ source_set("v8_base") {
     "src/ostreams.h",
     "src/parser.cc",
     "src/parser.h",
+    "src/perf-jit.cc",
+    "src/perf-jit.h",
     "src/preparse-data-format.h",
     "src/preparse-data.cc",
     "src/preparse-data.h",