[filebrowser] Introduce View action for supported file types (e.g. pdf).

chrome/browser/chromeos/extensions/file_browser_private_api.cc

Index: chrome/browser/chromeos/extensions/file_browser_private_api.cc
===================================================================
--- chrome/browser/chromeos/extensions/file_browser_private_api.cc	(revision 125140)
+++ chrome/browser/chromeos/extensions/file_browser_private_api.cc	(working copy)
@@ -1781,6 +1781,9 @@
   SET_STRING(IDS_FILE_BROWSER, MOUNT_ARCHIVE);
   SET_STRING(IDS_FILE_BROWSER, FORMAT_DEVICE);
 
+  SET_STRING(IDS_FILE_BROWSER, OPEN_ACTION);
+  SET_STRING(IDS_FILE_BROWSER, INSTALL_CRX);
+
   SET_STRING(IDS_FILE_BROWSER, GALLERY);
   SET_STRING(IDS_FILE_BROWSER, GALLERY_EDIT);
   SET_STRING(IDS_FILE_BROWSER, GALLERY_SHARE);
@@ -1912,6 +1915,10 @@
   SET_STRING(IDS_FILE_BROWSER, ENQUEUE);
 #undef SET_STRING
 
+  dict->SetString("PDF_VIEW_ENABLED",
+      file_manager_util::ShouldBeOpenedWithPdfPlugin(".pdf") ?
+          "true" : "false");
+
   ChromeURLDataManager::DataSource::SetFontAndTextDirection(dict);
 
   dict->SetString("PLAY_MEDIA",