Link Blink into the browser process less.

components/safe_json/BUILD.gn

Index: components/safe_json/BUILD.gn
diff --git a/components/safe_json/BUILD.gn b/components/safe_json/BUILD.gn
index aa0922437f80eb7fb0e383a6b9d17182a90af7e2..73e5a7ae5a30d31648f9de09e5cb82c89256d84a 100644
--- a/components/safe_json/BUILD.gn
+++ b/components/safe_json/BUILD.gn
@@ -23,7 +23,7 @@ source_set("safe_json") {
   ]
 
   deps = [
-    ":safe_json_parser_message_filter",
+    ":messages",
     "//base",
     "//components/strings",
     "//content/public/browser",
@@ -70,16 +70,30 @@ source_set("test_support") {
   ]
 }
 
+# This is a separate source set so that it can be shared between safe_json
+# (which can be used from any process) and the message filter (which depends on
+# the utility process and hence indirectly Blink.
+source_set("messages") {
+  sources = [
+    "safe_json_parser_messages.cc",
+    "safe_json_parser_messages.h",
+  ]
+
+  deps = [
+    "//content/public/common",
+    "//ipc",
+  ]
+}
+
 # GYP version: components/safe_json.gypi:safe_json_parser_message_filter
 source_set("safe_json_parser_message_filter") {
   sources = [
     "safe_json_parser_message_filter.cc",
     "safe_json_parser_message_filter.h",
-    "safe_json_parser_messages.cc",
-    "safe_json_parser_messages.h",
   ]
 
   deps = [
+    ":messages",
     "//base",
     "//content/public/common",
     "//content/public/utility",