From 7aa211dd304c18fda57df8754c747fb694c0b33c Mon Sep 17 00:00:00 2001
From: koto <koto@google.com>
Date: Wed, 21 Aug 2019 09:35:23 -0700
Subject: [PATCH] Make Closure Trusted Types integration not require TrustedURL
 values, as they will soon be removed from the Trusted Types API -
 https://github.com/WICG/trusted-types/pull/204.

goog.createTrustedTypesPolicy will attempt to create a default policy allowing any value to be converted to TrustedURL.

RELNOTES: Trusted Types integrations will allow any value to be a TrustedURL via defensively creating a 'default' policy (to prepare for TrustedURL deprecation)

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=264626714
---
 closure/goog/base.js | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/closure/goog/base.js b/closure/goog/base.js
index 033ddfd457..cc1511eb57 100644
--- a/closure/goog/base.js
+++ b/closure/goog/base.js
@@ -4168,6 +4168,21 @@ goog.createTrustedTypesPolicy = function(name) {
   } catch (e) {
     goog.logToConsole_(e.message);
   }
+
+  // TrustedTypes API will deprecate TrustedURLs in Chrome 78. To prepare for
+  // that, and make the Closure code emulate the post-deprecation behavior
+  // of the API, we attempt to create a default policy that blesses any value
+  // to TrustedURL. This is a best-effort attempt. If that does not succeed,
+  // the application fails close - TrustedURL values will simply be required
+  // at all relevant sinks.
+  if (typeof TrustedURL !== 'undefined' && TrustedTypes.getPolicyNames &&
+      TrustedTypes.getPolicyNames().indexOf('default') === -1) {
+    try {
+      TrustedTypes.createPolicy('default', {createURL: goog.identity_}, true);
+    } catch (e) {
+      goog.logToConsole_(e.message);
+    }
+  }
   return policy;
 };