Include error status code in console message for non-CORS response.

Source/core/fetch/CrossOriginAccessControl.cpp

Index: Source/core/fetch/CrossOriginAccessControl.cpp
diff --git a/Source/core/fetch/CrossOriginAccessControl.cpp b/Source/core/fetch/CrossOriginAccessControl.cpp
index ddcb29c406424386cc69bfafc051b9d6f413c30a..76040fb3b778d27f4c9b3166a92af542822f4c2a 100644
--- a/Source/core/fetch/CrossOriginAccessControl.cpp
+++ b/Source/core/fetch/CrossOriginAccessControl.cpp
@@ -142,6 +142,14 @@ static bool isOriginSeparator(UChar ch)
     return isASCIISpace(ch) || ch == ',';
 }
 
+static bool isInterestingStatusCode(int statusCode)
+{
+    // Predicate that gates what status codes should be included in
+    // console error messages for responses containing no access
+    // control headers.
+    return statusCode >= 400;
+}
+
 bool passesAccessControlCheck(const ResourceResponse& response, StoredCredentials includeCredentials, SecurityOrigin* securityOrigin, String& errorDescription)
 {
     AtomicallyInitializedStatic(AtomicString&, accessControlAllowOrigin = *new AtomicString("access-control-allow-origin", AtomicString::ConstructFromLiteral));
@@ -165,6 +173,9 @@ bool passesAccessControlCheck(const ResourceResponse& response, StoredCredential
     } else if (accessControlOriginString != securityOrigin->toAtomicString()) {
         if (accessControlOriginString.isEmpty()) {
             errorDescription = "No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin '" + securityOrigin->toString() + "' is therefore not allowed access.";
+
+            if (isInterestingStatusCode(response.httpStatusCode()))
+                errorDescription.append(" The response had HTTP status code " + String::number(response.httpStatusCode()) + ".");
         } else if (accessControlOriginString.string().find(isOriginSeparator, 0) != kNotFound) {
             errorDescription = "The 'Access-Control-Allow-Origin' header contains multiple values '" + accessControlOriginString + "', but only one is allowed. Origin '" + securityOrigin->toString() + "' is therefore not allowed access.";
         } else {