Add flag for carrier switch to about:flags.

chrome/app/generated_resources.grd

Index: chrome/app/generated_resources.grd
diff --git a/chrome/app/generated_resources.grd b/chrome/app/generated_resources.grd
index 8e31cde202d500a372450cb496f3eb603c19e8bf..2d2afccb016063ec7a5d7b46d5b4e85430c8e752 100644
--- a/chrome/app/generated_resources.grd
+++ b/chrome/app/generated_resources.grd
@@ -6406,6 +6406,12 @@ Keep your key file in a safe place. You will need it to create new versions of y
       <message name="IDS_FLAGS_ENABLE_WEBKIT_TEXT_SUBPIXEL_POSITIONING_DESCRIPTION" desc="Description for the flag to set when subpixel text positioning is enabled on web pages.">
         Allows text glyphs on web pages to have X positions which aren't snapped to the pixel grid.
       </message>
+      <message name="IDS_FLAGS_ENABLE_CARRIER_SWITCHING" desc="Name for the flag to set to enable mobile carrier switching.">
+        Enable switching between mobile carriers.
+      </message>
+      <message name="IDS_FLAGS_ENABLE_CARRIER_SWITCHING_DESCRIPTION" desc="Description for the flag to set to enable carrier switching.">
+        Allows the user to switch between mobile carriers from the UI.
+      </message>
       <message name="IDS_FLAGS_ENABLE_REQUEST_TABLET_SITE_NAME" desc="Name for the flag to set to enable Request Tablet Site in the wrench menu.">
         Enables the request tablet site option in the settings menu.
       </message>