Anchor element's referrer attribute implementation for Referrer Policy

Source/core/html/HTMLAnchorElement.cpp

Index: Source/core/html/HTMLAnchorElement.cpp
diff --git a/Source/core/html/HTMLAnchorElement.cpp b/Source/core/html/HTMLAnchorElement.cpp
index 59c3697985672a09cd15bb8b49d6d8e2cf86a226..716274c128629aed1c793f96e7da5c3c537c8d94 100644
--- a/Source/core/html/HTMLAnchorElement.cpp
+++ b/Source/core/html/HTMLAnchorElement.cpp
@@ -38,6 +38,7 @@
 #include "core/page/Chrome.h"
 #include "core/page/ChromeClient.h"
 #include "platform/network/NetworkHints.h"
+#include "platform/weborigin/ReferrerPolicy.h"
 
 namespace blink {
 
@@ -358,8 +359,22 @@ void HTMLAnchorElement::handleClick(Event* event)
         request.setRequestContext(WebURLRequest::RequestContextHyperlink);
         FrameLoadRequest frameRequest(&document(), request, getAttribute(targetAttr));
         frameRequest.setTriggeringEvent(event);
-        if (hasRel(RelationNoReferrer))
-            frameRequest.setShouldSendReferrer(NeverSendReferrer);
+
+        // TODO(burnik): Most of this section should be reused for any other type of navigation and resource loading.
+        // Inherit the policy from the document.
+        ReferrerPolicy referrerPolicyForRequest = document().referrerPolicy();
+        // We keep it strict. If there is a rel attribute saying 'noreferrer', that takes precedence.
+        if (hasRel(RelationNoReferrer)) {
+            referrerPolicyForRequest = ReferrerPolicyNever;
+        } else if (hasAttribute(referrerAttr)) {
+            const AtomicString& referrerPolicy = fastGetAttribute(referrerAttr);
+            if (!ParseReferrerPolicy(referrerPolicy.string(), &referrerPolicyForRequest)) {
+                // TODO(burnik): Possibly add a warning to the console?
+                ASSERT(referrerPolicyForRequest == document().referrerPolicy());
+            }
+        }
+
+        frameRequest.setReferrerPolicyForRequest(referrerPolicyForRequest);
         frame->loader().load(frameRequest);
     }
 }