Log a console warning when PortalNavigationThrottle blocks a request.

Bug: 1013389
Change-Id: I71e8a014660b6144c7f8a13c11bb6e692e331487
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1937856
Commit-Queue: Jeremy Roman <jbroman@chromium.org>
Commit-Queue: Kevin McNee <mcnee@chromium.org>
Auto-Submit: Jeremy Roman <jbroman@chromium.org>
Reviewed-by: Kevin McNee <mcnee@chromium.org>
Cr-Commit-Position: refs/heads/master@{#719384}

content/browser/portal/portal_navigation_throttle.cc

@@ -6,6 +6,7 @@
 
 #include "base/feature_list.h"
 #include "base/memory/ptr_util.h"
+#include "base/strings/stringprintf.h"
 #include "content/browser/frame_host/render_frame_host_impl.h"
 #include "content/browser/portal/portal.h"
 #include "content/browser/web_contents/web_contents_impl.h"
@@ -64,7 +65,17 @@ PortalNavigationThrottle::WillStartOrRedirectRequest() {
   url::Origin first_party_origin =
       portal->owner_render_frame_host()->GetLastCommittedOrigin();
 
-  return origin == first_party_origin ? PROCEED : BLOCK_REQUEST;
+  if (origin == first_party_origin)
+    return PROCEED;
+
+  // TODO(crbug.com/1013389): Update this message to refer to external
+  // documentation if we write any.
+  portal->owner_render_frame_host()->AddMessageToConsole(
+      blink::mojom::ConsoleMessageLevel::kWarning,
+      base::StringPrintf("Navigating a portal to cross-origin content (from "
+                         "%s) is not currently permitted and was blocked.",
+                         origin.Serialize().c_str()));
+  return BLOCK_REQUEST;
 }
 
 }  // namespace content

content/browser/portal/portal_navigation_throttle_browsertest.cc

@@ -20,6 +20,7 @@
 #include "net/test/embedded_test_server/embedded_test_server.h"
 #include "net/test/embedded_test_server/http_request.h"
 #include "net/test/embedded_test_server/request_handler_util.h"
+#include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/blink/public/common/features.h"
 #include "url/gurl.h"
@@ -247,5 +248,27 @@ IN_PROC_BROWSER_TEST_F(PortalNavigationThrottleBrowserTest,
   EXPECT_EQ(portal->GetPortalContents()->GetLastCommittedURL(), redirect_url);
 }
 
+IN_PROC_BROWSER_TEST_F(PortalNavigationThrottleBrowserTest,
+                       LogsConsoleWarning) {
+  ASSERT_TRUE(NavigateToURL(
+      GetWebContents(),
+      embedded_test_server()->GetURL("portal.test", "/title1.html")));
+
+  auto* old_delegate = GetWebContents()->GetDelegate();
+  ConsoleObserverDelegate console_delegate(GetWebContents(),
+                                           "*portal*cross-origin*");
+  GetWebContents()->SetDelegate(&console_delegate);
+
+  Portal* portal = InsertAndWaitForPortal(
+      embedded_test_server()->GetURL("not.portal.test", "/title2.html"),
+      /*expected_to_succeed=*/false);
+  EXPECT_NE(portal, nullptr);
+
+  console_delegate.Wait();
+  EXPECT_THAT(console_delegate.message(),
+              ::testing::HasSubstr("http://not.portal.test"));
+  GetWebContents()->SetDelegate(old_delegate);
+}
+
 }  // namespace
 }  // namespace content