media: Rename MojoMediaApplication to MediaService

media/media_options.gni

Index: media/media_options.gni
diff --git a/media/media_options.gni b/media/media_options.gni
index 61dac760ac3aad5cda26b90799147d60ad743515..1ea2acf362bef24ebd440241c569ef4a60d9d254 100644
--- a/media/media_options.gni
+++ b/media/media_options.gni
@@ -89,12 +89,12 @@ declare_args() {
   #                    Renderer. Cannot be used with the mojo Renderer above.
   mojo_media_services = []
 
-  # The process to host the mojo media application.
+  # The process to host the mojo media service.
   # Valid options are:
-  # - "none": Do not use mojo media application.
-  # - "browser": Use mojo media application hosted in the browser process.
-  # - "gpu": Use mojo media application hosted in the gpu process.
-  # - "utility": Use mojo media application hosted in the utility process.
+  # - "none": Do not use mojo media service.
+  # - "browser": Use mojo media service hosted in the browser process.
+  # - "gpu": Use mojo media service hosted in the gpu process.
+  # - "utility": Use mojo media service hosted in the utility process.
   mojo_media_host = "none"
 
   # Default mojo_media_services and mojo_media_host on various platforms.