Files.app: Enable externalfile: protocol for MTP volumes.

chrome/browser/chromeos/file_manager/open_with_browser.cc

Index: chrome/browser/chromeos/file_manager/open_with_browser.cc
diff --git a/chrome/browser/chromeos/file_manager/open_with_browser.cc b/chrome/browser/chromeos/file_manager/open_with_browser.cc
index 429883c198b362e8151ae305c2ffa1f6cd5350e2..0fbc917b1897e5266a488ae6e248f19243ec6b78 100644
--- a/chrome/browser/chromeos/file_manager/open_with_browser.cc
+++ b/chrome/browser/chromeos/file_manager/open_with_browser.cc
@@ -129,20 +129,22 @@ GURL ReadUrlFromGDocOnBlockingPool(const base::FilePath& file_path) {
 
 }  // namespace
 
-bool OpenFileWithBrowser(Profile* profile, const base::FilePath& file_path) {
+bool OpenFileWithBrowser(Profile* profile,
+                         const storage::FileSystemURL& file_system_url) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   DCHECK(profile);
 
+  const base::FilePath file_path = file_system_url.path();
+
   // For things supported natively by the browser, we should open it
   // in a tab.
   if (IsViewableInBrowser(file_path) ||
       ShouldBeOpenedWithPlugin(profile, file_path.Extension())) {
-    GURL page_url = net::FilePathToFileURL(file_path);
-    // Override drive resource to point to internal handler instead of file URL.
-    if (drive::util::IsUnderDriveMountPoint(file_path)) {
-      page_url = chromeos::FilePathToExternalFileURL(
-          drive::util::ExtractDrivePath(file_path));
-    }
+    // Use external file URL if it is provided for the file system.
+    GURL page_url = chromeos::FileSystemURLToExternalFileURL(file_system_url);
+    if (page_url.is_empty())
+      page_url = net::FilePathToFileURL(file_system_url.path());
+
     OpenNewTab(profile, page_url);
     return true;
   }
@@ -150,8 +152,8 @@ bool OpenFileWithBrowser(Profile* profile, const base::FilePath& file_path) {
   if (drive::util::HasHostedDocumentExtension(file_path)) {

[mtomasz, 2014/09/25 06:48:09]

Do we need this "HasHostedDocumentExtension()" check? It works only for Drive,
not other file systems.

[hirono, 2014/09/25 07:38:07]

Actually, if drive hosted files (e.g. gdoc) are located in Downloads directory,
they can be opened thanks to this check.
Maybe we can remove this after solving crbug.com/414555.

     if (drive::util::IsUnderDriveMountPoint(file_path)) {

[mtomasz, 2014/09/25 06:48:09]

Similarly, do we need this IsUnderDriveMountPoint check? Shouldn't we just check
if |url| returned in #155 is empty?

[hirono, 2014/09/25 07:38:07]

If a file is under the drive, we have redirection in DriveBackendDelegate for
the hosted file, and ExternalFileProtocolHandler use it.
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/browser/chr...

Otherwise, we obtain the hosted URL by parsing the contents of files in
ReadUrlFromGDocOnBlockingPool.

       // The file is on Google Docs. Open with drive URL.
-      GURL url = chromeos::FilePathToExternalFileURL(
-          drive::util::ExtractDrivePath(file_path));
+      GURL url = chromeos::FileSystemURLToExternalFileURL(file_system_url);
+      DCHECK(!url.is_empty());
       OpenNewTab(profile, url);
     } else {
       // The file is local (downloaded from an attachment or otherwise copied).