Pass document policies into Policy Container by const reference

Initially, this parameter was just an enum, so we were passing it by
value. Now it became a struct, so we should pass it by const
reference.

Bug: 1130587
Change-Id: I6c02e4453259914c01a7d6c218be66cc5af30ad3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2616560
Auto-Submit: Antonio Sartori <antoniosartori@chromium.org>
Reviewed-by: Arthur Sonzogni <arthursonzogni@chromium.org>
Commit-Queue: Arthur Sonzogni <arthursonzogni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#841487}

content/browser/renderer_host/policy_container_host.cc

@@ -8,7 +8,7 @@ namespace content {
 
 PolicyContainerHost::PolicyContainerHost() = default;
 PolicyContainerHost::PolicyContainerHost(
-    PolicyContainerHost::DocumentPolicies document_policies)
+    const PolicyContainerHost::DocumentPolicies& document_policies)
     : document_policies_(document_policies) {}
 PolicyContainerHost::~PolicyContainerHost() = default;
 

content/browser/renderer_host/policy_container_host.h

@@ -41,7 +41,7 @@ class CONTENT_EXPORT PolicyContainerHost
   };
 
   PolicyContainerHost();
-  explicit PolicyContainerHost(DocumentPolicies document_policies);
+  explicit PolicyContainerHost(const DocumentPolicies& document_policies);
   PolicyContainerHost(const PolicyContainerHost&) = delete;
   PolicyContainerHost& operator=(const PolicyContainerHost&) = delete;
   ~PolicyContainerHost() override;