Add ReferrerPolicy to the PolicyContainer

https://bugs.webkit.org/show_bug.cgi?id=244561

Reviewed by Brent Fulgham.

The HTML spec calls for ReferrerPolicy to be in the PolicyContainer
struct.[1] This adds the ReferrerPolicy enum to the PolicyContainer
struct to keep our implementation more in line with the spec.

This also shuffles around the virtual referrerPolicy getter so the
SecurityContext can construct a PolicyContainer given the implementation
from its subclasses.

No new tests, ReferrerPolicy already covered by existing tests.

[1] https://html.spec.whatwg.org/multipage/origin.html#policy-containers

* Source/WebCore/dom/ScriptExecutionContext.h:
* Source/WebCore/dom/SecurityContext.cpp:
(WebCore::SecurityContext::policyContainer const):
* Source/WebCore/dom/SecurityContext.h:
* Source/WebCore/loader/PolicyContainer.h:
(WebCore::PolicyContainer::isolatedCopy const):
(WebCore::PolicyContainer::isolatedCopy):
(WebCore::operator==):
(WebCore::PolicyContainer::encode const):
(WebCore::PolicyContainer::decode):

Canonical link: https://commits.webkit.org/254003@main

Source/WebCore/dom/ScriptExecutionContext.h

@@ -78,7 +78,6 @@ class ResourceRequest;
 class SocketProvider;
 class WebCoreOpaqueRoot;
 enum class LoadedFromOpaqueSource : uint8_t;
-enum class ReferrerPolicy : uint8_t;
 enum class TaskSource : uint8_t;
 
 #if ENABLE(NOTIFICATIONS)
@@ -115,8 +114,6 @@ class ScriptExecutionContext : public SecurityContext, public CanMakeWeakPtr<Scr
 
     virtual String userAgent(const URL&) const = 0;
 
-    virtual ReferrerPolicy referrerPolicy() const = 0;
-
     virtual const Settings::Values& settingsValues() const = 0;
 
     virtual NotificationClient* notificationClient() { return nullptr; }

Source/WebCore/dom/SecurityContext.cpp

@@ -174,7 +174,8 @@ PolicyContainer SecurityContext::policyContainer() const
 {
     return {
         crossOriginEmbedderPolicy(),
-        crossOriginOpenerPolicy()
+        crossOriginOpenerPolicy(),
+        referrerPolicy()
     };
 }
 

Source/WebCore/dom/SecurityContext.h

@@ -40,6 +40,7 @@ class SecurityOriginPolicy;
 class ContentSecurityPolicy;
 struct CrossOriginOpenerPolicy;
 struct PolicyContainer;
+enum class ReferrerPolicy : uint8_t;
 
 enum SandboxFlag {
     // See http://www.whatwg.org/specs/web-apps/current-work/#attr-iframe-sandbox for a list of the sandbox flags.
@@ -96,6 +97,8 @@ class SecurityContext {
 
     virtual const CrossOriginOpenerPolicy& crossOriginOpenerPolicy() const;
 
+    virtual ReferrerPolicy referrerPolicy() const = 0;
+
     PolicyContainer policyContainer() const;
 
     WEBCORE_EXPORT SecurityOrigin* securityOrigin() const;

Source/WebCore/loader/PolicyContainer.h

@@ -34,23 +34,24 @@ namespace WebCore {
 struct PolicyContainer {
     CrossOriginEmbedderPolicy crossOriginEmbedderPolicy;
     CrossOriginOpenerPolicy crossOriginOpenerPolicy;
-    // FIXME: CSP list and referrer policy should be part of the PolicyContainer.
+    ReferrerPolicy referrerPolicy = ReferrerPolicy::Default;
+    // FIXME: CSP list should be part of the PolicyContainer.
 
-    PolicyContainer isolatedCopy() const & { return { crossOriginEmbedderPolicy.isolatedCopy(), crossOriginOpenerPolicy.isolatedCopy() }; }
-    PolicyContainer isolatedCopy() && { return { WTFMove(crossOriginEmbedderPolicy).isolatedCopy(), WTFMove(crossOriginOpenerPolicy).isolatedCopy() }; }
+    PolicyContainer isolatedCopy() const & { return { crossOriginEmbedderPolicy.isolatedCopy(), crossOriginOpenerPolicy.isolatedCopy(), referrerPolicy }; }
+    PolicyContainer isolatedCopy() && { return { WTFMove(crossOriginEmbedderPolicy).isolatedCopy(), WTFMove(crossOriginOpenerPolicy).isolatedCopy(), referrerPolicy }; }
     template<class Encoder> void encode(Encoder&) const;
     template<class Decoder> static std::optional<PolicyContainer> decode(Decoder&);
 };
 
 inline bool operator==(const PolicyContainer& a, const PolicyContainer& b)
 {
-    return a.crossOriginEmbedderPolicy == b.crossOriginEmbedderPolicy && a.crossOriginOpenerPolicy == b.crossOriginOpenerPolicy;
+    return a.crossOriginEmbedderPolicy == b.crossOriginEmbedderPolicy && a.crossOriginOpenerPolicy == b.crossOriginOpenerPolicy && a.referrerPolicy == b.referrerPolicy;
 }
 
 template<class Encoder>
 void PolicyContainer::encode(Encoder& encoder) const
 {
-    encoder << crossOriginEmbedderPolicy << crossOriginOpenerPolicy;
+    encoder << crossOriginEmbedderPolicy << crossOriginOpenerPolicy << referrerPolicy;
 }
 
 template<class Decoder>
@@ -66,9 +67,15 @@ std::optional<PolicyContainer> PolicyContainer::decode(Decoder& decoder)
     if (!crossOriginOpenerPolicy)
         return std::nullopt;
 
+    std::optional<ReferrerPolicy> referrerPolicy;
+    decoder >> referrerPolicy;
+    if (!referrerPolicy)
+        return std::nullopt;
+
     return {{
         WTFMove(*crossOriginEmbedderPolicy),
-        WTFMove(*crossOriginOpenerPolicy)
+        WTFMove(*crossOriginOpenerPolicy),
+        *referrerPolicy
     }};
 }