Add a policy for disabling the stripping of PAC URLs.

chrome/test/data/policy/policy_test_cases.json

Index: chrome/test/data/policy/policy_test_cases.json
diff --git a/chrome/test/data/policy/policy_test_cases.json b/chrome/test/data/policy/policy_test_cases.json
index 930382bb780737568bb9cf54651f886b9af922e1..dea68c0493d38560ef09b1f30b834caf543a0038 100644
--- a/chrome/test/data/policy/policy_test_cases.json
+++ b/chrome/test/data/policy/policy_test_cases.json
@@ -1767,6 +1767,16 @@
     ]
   },
 
+  "PacHttpsUrlStrippingEnabled": {
+    "os": ["win", "linux", "mac", "chromeos"],
+    "test_policy": { "PacHttpsUrlStrippingEnabled": true },
+    "pref_mappings": [
+      { "pref": "proxy.pac_https_url_stripping_enabled",
+        "local_state": true
+      }
+    ]
+  },
+
   "RegisteredProtocolHandlers": {
     "os": ["win", "linux", "mac", "chromeos"],
     "can_be_recommended": true,