Video Player: Add a flag to support chromecast

chrome/app/chromeos_strings.grdp

 <?xml version="1.0" encoding="utf-8"?>
 <!-- ChromeOS-specific strings (included from generated_resources.grd).
      Everything in this file is wrapped in <if expr="chromeos">. -->
 <grit-part>
   <message name="IDS_EMPTY_STRING" desc="Empty string, exist only to make code generic. No translation required.">
   </message>
   <message name="IDS_CHROMEBOOK" desc="The localized name for Chromebook.">
     Chromebook
   </message>
   <message name="IDS_CHROMEBOX" desc="The localized name for Chromebox">
@@ skipping 114 matching lines @@
   </message>
   <message name="IDS_FLAGS_ENABLE_FILE_MANAGER_MTP_DESCRIPTION" desc="Description of the about:flag option to the enable MTP support in file manager.">
     Show MTP devices as a file storage in the file manager.
   </message>
   <message name="IDS_FLAGS_FILE_MANAGER_ENABLE_NEW_GALLERY_NAME" desc="Name of the about:flag option to enable the new gallery app.">
     Enable the new gallery
   </message>
   <message name="IDS_FLAGS_FILE_MANAGER_ENABLE_NEW_GALLERY_DESCRIPTION" desc="Description of the about:flag option to the enable new gallery app.">
     Use the experimental new gallery instead of the stable one.
   </message>
+  <message name="IDS_FLAGS_ENABLE_VIDEO_PLAYER_CHROMECAST_SUPPORT_NAME" desc="Name of the about:flag option to enable the chromecast support for video app.">
+    Experimental Chromecast support for Video Player
+  </message>
+  <message name="IDS_FLAGS_ENABLE_VIDEO_PLAYER_CHROMECAST_SUPPORT_DESCRIPTION" desc="Description of the about:flag option to the enable the chromecast support for video app.">
+    This option enables experimental Chromecast support for Video Player app on ChromeOS.
+  </message>
   <message name="IDS_FILE_SYSTEM_PROVIDER_UNRESPONSIVE_WARNING" desc="A warning shown in a notification that an operation is taking longer than expected.">
     An operation is taking longer than expected. Do you want to abort it?
   </message>
   <message name="IDS_FILE_SYSTEM_PROVIDER_MANY_UNRESPONSIVE_WARNING" desc="A warning shown in a notification that more than one operations are taking longer than expected.">
     Some operations are taking longer than expected. Do you want to abort them?
   </message>
   <message name="IDS_FILE_SYSTEM_PROVIDER_UNRESPONSIVE_ABORT_BUTTON" desc="Label of the button on the notification about an operation(s) taking to long.">
     Abort
   </message>
   <message name="IDS_FILE_BROWSER_ARCHIVE_DIRECTORY_LABEL" desc="/archive directory label.">
@@ skipping 5415 matching lines @@
   </message>
 
   <!-- 'OK Google' voice search activation display strings -->
   <message name="IDS_FLAGS_OK_GOOGLE_NAME" desc="Name of about:flags option for Ok Google.">
     Enable 'Ok Google' to activate voice search.
   </message>
   <message name="IDS_FLAGS_OK_GOOGLE_DESCRIPTION" desc="Description of about:flags option Ok Google.">
     If enabled, there will be an option in chrome:settings to enable saying 'Ok Google' to activate voice search.
   </message>
 </grit-part>