Default page title (the page's URL) is now in an LTR embedding.

Only affects URLs with strong right-to-left characters.

This fixes the case where the URL contains RTL characters, causing the
components of the URL to be rendered from right to left. The display is
now consistent with the Omnibox display of URLs and compliant with RFC
3987.

BUG=630481
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation

Review-Url: https://codereview.chromium.org/2176463002
Cr-Commit-Position: refs/heads/master@{#408920}

content/browser/frame_host/navigation_entry_impl.cc

@@ -10,6 +10,7 @@
 #include <utility>
 
 #include "base/debug/dump_without_crashing.h"
+#include "base/i18n/rtl.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/string_util.h"
@@ -418,6 +419,12 @@ const base::string16& NavigationEntryImpl::GetTitleForDisplay() const {
     base::string16::size_type slashpos = title.rfind('/', lastpos);
     if (slashpos != base::string16::npos)
       title = title.substr(slashpos + 1);
+  } else if (base::i18n::StringContainsStrongRTLChars(title)) {
+    // Wrap the URL in an LTR embedding for proper handling of RTL characters.
+    // (RFC 3987 Section 4.1 states that "Bidirectional IRIs MUST be rendered in
+    // the same way as they would be if they were in a left-to-right
+    // embedding".)
+    base::i18n::WrapStringWithLTRFormatting(&title);
   }
 
   gfx::ElideString(title, kMaxTitleChars, &cached_display_title_);

content/browser/frame_host/navigation_entry_impl_unittest.cc

@@ -67,13 +67,27 @@ TEST_F(NavigationEntryTest, NavigationEntryURLs) {
   entry1_->SetURL(GURL("http://www.google.com"));
   EXPECT_EQ(GURL("http://www.google.com"), entry1_->GetURL());
   EXPECT_EQ(GURL("http://www.google.com"), entry1_->GetVirtualURL());
-  EXPECT_EQ(ASCIIToUTF16("www.google.com"),
+  EXPECT_EQ(ASCIIToUTF16("www.google.com"), entry1_->GetTitleForDisplay());
+
+  // Setting URL with RTL characters causes it to be wrapped in an LTR
+  // embedding.
+  entry1_->SetURL(GURL("http://www.xn--rgba6eo.com"));
+  EXPECT_EQ(base::WideToUTF16(L"\x202a"
+                              L"www.\x062c\x0648\x062c\x0644"
+                              L".com\x202c"),
             entry1_->GetTitleForDisplay());
 
   // file:/// URLs should only show the filename.
   entry1_->SetURL(GURL("file:///foo/bar baz.txt"));
   EXPECT_EQ(ASCIIToUTF16("bar baz.txt"), entry1_->GetTitleForDisplay());
 
+  // file:/// URLs should *not* be wrapped in an LTR embedding.
+  entry1_->SetURL(GURL("file:///foo/%D8%A7%D8%A8 %D8%AC%D8%AF.txt"));
+  EXPECT_EQ(base::WideToUTF16(L"\x0627\x0628"
+                              L" \x062c\x062f"
+                              L".txt"),
+            entry1_->GetTitleForDisplay());
+
   // For file:/// URLs, make sure that slashes after the filename are ignored.
   // Regression test for https://crbug.com/503003.
   entry1_->SetURL(GURL("file:///foo/bar baz.txt#foo/bar"));