Certificate Transparency: Add STH Fetching capability.

components/certificate_transparency/BUILD.gn

Index: components/certificate_transparency/BUILD.gn
diff --git a/chrome/installer/launcher_support/BUILD.gn b/components/certificate_transparency/BUILD.gn
similarity index 59%
copy from chrome/installer/launcher_support/BUILD.gn
copy to components/certificate_transparency/BUILD.gn
index 9abab50df0aefabdc299b6795e0fee8f77ee83f2..1619d54ddcdf11f3989f520a9573b87ec1909315 100644
--- a/chrome/installer/launcher_support/BUILD.gn
+++ b/components/certificate_transparency/BUILD.gn
@@ -2,13 +2,15 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-source_set("launcher_support") {
+static_library("certificate_transparency") {
   sources = [
-    "chrome_launcher_support.cc",
-    "chrome_launcher_support.h",
+    "log_proof_fetcher.cc",
+    "log_proof_fetcher.h",
   ]
 
   deps = [
     "//base",
+    "//components/safe_json",
+    "//net",
   ]
 }