Add some public_deps for //headless:headless_lib.

headless/BUILD.gn

Index: headless/BUILD.gn
diff --git a/headless/BUILD.gn b/headless/BUILD.gn
index 6345e098a44e826849f1c47b48357d3ed5478f6c..00023323909fd58a17344ec3d6a35d0fa03ee37f 100644
--- a/headless/BUILD.gn
+++ b/headless/BUILD.gn
@@ -301,10 +301,14 @@ static_library("headless_lib") {
     ]
   }
 
+  public_deps = [
+    "//base",
+    "//net",
+  ]
+
   deps = [
     ":gen_devtools_client_api",
     ":version_header",
-    "//base",
     "//components/crash/content/browser",
     "//components/security_state/content",
     "//components/security_state/core",
@@ -313,7 +317,6 @@ static_library("headless_lib") {
     "//content/public/child:child",
     "//content/public/common",
     "//content/public/common:service_names",
-    "//net",
     "//services/service_manager/public/cpp",
     "//third_party/mesa:osmesa",
     "//ui/base",