Don't abort the PDF stream if a navigation is intiated within the same page.

If a PDF file is loaded via a link click with a history.replacestate call
in the pagehide/pageshow event for the main html page, we get a DidStartNavigation
notification on the guest webcontents created for the EmbeddedObserver.
Currently we abort the stream if it is a top level navigation.
It seems like we should not abort the stream if the navigation is within the same page.

The problem does not occur if the PDF is opened in a different tab or window

Should fix the black PDF issues with M55.

BUG=677580
TEST=Covered by browser test PDFExtensionTest.OpenPDFOnLinkClickWithReplaceState

Review-Url: https://codereview.chromium.org/2611643004
Cr-Commit-Position: refs/heads/master@{#441857}

chrome/browser/pdf/pdf_extension_test.cc

@@ -48,6 +48,7 @@
 #include "content/public/browser/render_widget_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/test/browser_test_utils.h"
+#include "content/public/test/test_navigation_observer.h"
 #include "extensions/browser/extension_registry.h"
 #include "extensions/common/manifest_handlers/mime_types_handler.h"
 #include "extensions/test/result_catcher.h"
@@ -932,3 +933,67 @@ IN_PROC_BROWSER_TEST_F(PDFExtensionTest, NavigationOnCorrectTab) {
   EXPECT_TRUE(web_contents->GetController().GetPendingEntry());
   EXPECT_FALSE(active_web_contents->GetController().GetPendingEntry());
 }
+
+// This test opens a PDF by clicking a link via javascript and verifies that
+// the PDF is loaded and functional by clicking a link in the PDF. The link
+// click in the PDF opens a new tab. The main page handles the pageShow event
+// and updates the history state.
+IN_PROC_BROWSER_TEST_F(PDFExtensionTest, OpenPDFOnLinkClickWithReplaceState) {
+  host_resolver()->AddRule("www.example.com", "127.0.0.1");
+
+  // Navigate to the main page.
+  GURL test_url(
+      embedded_test_server()->GetURL("/pdf/pdf_href_replace_state.html"));
+  ui_test_utils::NavigateToURL(browser(), test_url);
+  content::WebContents* web_contents =
+      browser()->tab_strip_model()->GetActiveWebContents();
+  ASSERT_TRUE(web_contents);
+
+  // Click on the link which opens the PDF via JS.
+  content::TestNavigationObserver navigation_observer(web_contents);
+  const char kPdfLinkClick[] = "document.getElementById('link').click();";
+  ASSERT_TRUE(content::ExecuteScript(web_contents->GetRenderViewHost(),
+                                     kPdfLinkClick));
+  navigation_observer.Wait();
+  const GURL& current_url = web_contents->GetURL();
+  ASSERT_TRUE(current_url.path() == "/pdf/test-link.pdf");
+
+  ASSERT_TRUE(pdf_extension_test_util::EnsurePDFHasLoaded(web_contents));
+
+  // Now click on the link to example.com in the PDF. This should open up a new
+  // tab.
+  content::BrowserPluginGuestManager* guest_manager =
+      web_contents->GetBrowserContext()->GetGuestManager();
+  content::WebContents* guest_contents =
+      guest_manager->GetFullPageGuest(web_contents);
+  ASSERT_TRUE(guest_contents);
+  // The link position of the test-link.pdf in page coordinates is (110, 110).
+  // Convert the link position from page coordinates to screen coordinates.
+  gfx::Point link_position(110, 110);
+  ConvertPageCoordToScreenCoord(guest_contents, &link_position);
+
+  content::WindowedNotificationObserver observer(
+      chrome::NOTIFICATION_TAB_ADDED,
+      content::NotificationService::AllSources());
+  content::SimulateMouseClickAt(web_contents, kDefaultKeyModifier,
+                                blink::WebMouseEvent::Button::Left,
+                                link_position);
+  observer.Wait();
+
+  // We should have two tabs now. One with the PDF and the second for
+  // example.com
+  int tab_count = browser()->tab_strip_model()->count();
+  ASSERT_EQ(2, tab_count);
+
+  content::WebContents* active_web_contents =
+      browser()->tab_strip_model()->GetActiveWebContents();
+  ASSERT_EQ(web_contents, active_web_contents);
+
+  content::WebContents* new_web_contents =
+      browser()->tab_strip_model()->GetWebContentsAt(1);
+  ASSERT_TRUE(new_web_contents);
+  ASSERT_NE(web_contents, new_web_contents);
+
+  const GURL& url = new_web_contents->GetURL();
+  ASSERT_EQ(GURL("http://www.example.com"), url);
+}

chrome/test/data/pdf/pdf_href_replace_state.html

+<html>
+<head>
+<title>First window</title>
+<script>
+window.addEventListener('pagehide', function() {
+  history.replaceState({time: Date.now()}, '');
+});
+</script>
+</head>
+
+<body>
+<a id="link" href="test-link.pdf"> pdf </a>
+</body>
+</html>

extensions/browser/guest_view/mime_handler_view/mime_handler_stream_manager.cc

@@ -223,7 +223,7 @@ void MimeHandlerStreamManager::EmbedderObserver::
 void MimeHandlerStreamManager::EmbedderObserver::DidStartNavigation(
     content::NavigationHandle* navigation_handle) {
   // If the top level frame is navigating away, clean up the stream.
-  if (navigation_handle->IsInMainFrame())
+  if (navigation_handle->IsInMainFrame() && !navigation_handle->IsSamePage())
     AbortStream();
 }