Remove const qualifiers from Drive/GData files to avoid compile errors on Mac buildbots

chrome/browser/chromeos/gdata/drive_api_parser.h

Index: chrome/browser/chromeos/gdata/drive_api_parser.h
diff --git a/chrome/browser/chromeos/gdata/drive_api_parser.h b/chrome/browser/chromeos/gdata/drive_api_parser.h
index 2aa10310a51885d45a423203f500daba1c49f300..46f9cc3f0ba0eadd5c8b7988390874d529c10abd 100644
--- a/chrome/browser/chromeos/gdata/drive_api_parser.h
+++ b/chrome/browser/chromeos/gdata/drive_api_parser.h
@@ -97,7 +97,7 @@ class DriveAppIcon {
   IconCategory category() const { return category_; }
 
   // Size in pixels of one side of the icon (icons are always square).
-  const int icon_side_length() const { return icon_side_length_; }
+  int icon_side_length() const { return icon_side_length_; }
 
   // Returns URL for this icon.
   const GURL& icon_url() const { return icon_url_; }