Implement media Cast button in Blink

webkit/glue/webkit_strings.grd

Index: webkit/glue/webkit_strings.grd
diff --git a/webkit/glue/webkit_strings.grd b/webkit/glue/webkit_strings.grd
index 02cd4b41f1bf74dc42775d1a09f600272198d784..8d110f97acebf27886a2cc49bfd8cd9b0857dbe1 100644
--- a/webkit/glue/webkit_strings.grd
+++ b/webkit/glue/webkit_strings.grd
@@ -447,6 +447,14 @@ below:
       <message name="IDS_AX_MEDIA_HIDE_CLOSED_CAPTIONS_BUTTON" desc="accessibility role description for hide closed captions button">
         hide closed captions
       </message>
+      
+      <message name="IDS_AX_MEDIA_CAST_OFF_BUTTON" desc="accessibility role description for remote playback button">

[michaeln, 2014/08/05 00:54:49]

lgtm

nit: the names of these sound like the buttons provide an on/off switch for
'casting', but it doesn't look like that in a quick reading of the cc code. if
that's right, consider renaming to better reflect the functionality.

[aberent, 2014/08/05 20:49:07]

This comes from Android O.S. usage, although the most recent version of the
Android downloadable resources seem to use the terms 'media_route_on' and
'media_route_off'

+        play on remote device
+      </message>
+      
+      <message name="IDS_AX_MEDIA_CAST_ON_BUTTON" desc="accessibility role description for remote playback control button">
+        control remote playback
+      </message>
 
       <message name="IDS_AX_MEDIA_AUDIO_ELEMENT_HELP" desc="Accessible help of audio controls">
         audio
@@ -508,6 +516,14 @@ below:
         stop displaying closed captions
       </message>
 
+      <message name="IDS_AX_MEDIA_CAST_OFF_BUTTON_HELP" desc="accessibility help description for remote playback button">
+        play on remote device
+      </message>
+      
+      <message name="IDS_AX_MEDIA_CAST_ON_BUTTON_HELP" desc="accessibility help description for remote playback control button">
+        control remote playback
+      </message>
+
       <message name="IDS_AX_MILLISECOND_FIELD_TEXT" desc="Accessible description of the millisecond field in a date/time control">
         Milliseconds
       </message>