Allow PDF viewer to navigate to file: URLs

PDF viewer extension require navigation to file URLs, since some local
PDF files have links to file: URLs, which should be allowed.

(cherry picked from commit 70226cc)

Bug: 1490387
Change-Id: I286f5094ed3c4af6ffcfeec963170a8d38c4c526
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4920241
Auto-Submit: Jun Kokatsu <jkokatsu@google.com>
Reviewed-by: David Bertoni <dbertoni@chromium.org>
Commit-Queue: David Bertoni <dbertoni@chromium.org>
Cr-Original-Commit-Position: refs/heads/main@{#1207958}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4943758
Commit-Queue: Jun Kokatsu <jkokatsu@google.com>
Cr-Commit-Position: refs/branch-heads/5993@{#1308}
Cr-Branched-From: 5113507-refs/heads/main@{#1192594}

chrome/browser/extensions/extension_tab_util.cc

@@ -871,6 +871,8 @@ base::expected<GURL, std::string> ExtensionTabUtil::PrepareURLForNavigation(
   // navigation as such contexts are trusted and do not have a concept of file
   // access.
   if (extension && url.SchemeIsFile() &&
+      // PDF viewer extension can navigate to file URLs.
+      extension->id() != extension_misc::kPdfExtensionId &&
       !util::AllowFileAccess(extension->id(), browser_context) &&
       base::FeatureList::IsEnabled(
           extensions_features::kRestrictFileURLNavigation)) {

chrome/browser/extensions/extension_tab_util_unittest.cc

@@ -175,6 +175,18 @@ TEST_F(ChromeExtensionNavigationTest, PrepareURLForNavigation) {
   }
 }
 
+TEST_F(ChromeExtensionNavigationTest, PrepareURLForNavigationWithPDFViewer) {
+  // Set ID for PDF viewer extension.
+  auto extension =
+      ExtensionBuilder("test").SetID(extension_misc::kPdfExtensionId).Build();
+
+  // File URLs are returned when the extension has access to file.
+  const std::string kFileURLWithPDFViewer("file:///etc/passwd");
+  auto url = ExtensionTabUtil::PrepareURLForNavigation(
+      kFileURLWithPDFViewer, extension.get(), browser_context());
+  EXPECT_THAT(url, base::test::ValueIs(GURL(kFileURLWithPDFViewer)));
+}
+
 TEST_F(ChromeExtensionNavigationTest, PrepareURLForNavigationOnDevtools) {
   const std::string kDevtoolsURL(
       "devtools://devtools/bundled/devtools_app.html");