[gnome-builder] content-type: Add some build-systems icons

[Christian Hergert <chergert src gnome org>]

commit 40c3a04cb7e26d039e808bf7987a53133401da4f
Author: vanadiae <vanadiae35 gmail com>
Date:   Wed Dec 30 19:16:29 2020 +0100

    content-type: Add some build-systems icons
    
    It makes it easier to scan through the files in the project tree or in
    the opened files to find the build system files.

 src/libide/io/ide-content-type.c | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/src/libide/io/ide-content-type.c b/src/libide/io/ide-content-type.c
index 026965259..6a76f0ea3 100644
--- a/src/libide/io/ide-content-type.c
+++ b/src/libide/io/ide-content-type.c
@@ -87,6 +87,9 @@ ide_io_init_ctor (void)
   ADD_ICON (bundled_by_content_type, "text-x-script-symbolic", NULL);
   ADD_ICON (bundled_by_content_type, "text-x-vala-symbolic", NULL);
   ADD_ICON (bundled_by_content_type, "text-xml-symbolic", NULL);
+  ADD_ICON (bundled_by_content_type, "text-x-meson", "builder-build-symbolic");
+  ADD_ICON (bundled_by_content_type, "text-x-cmake", "builder-build-symbolic");
+  ADD_ICON (bundled_by_content_type, "text-x-makefile", "builder-build-symbolic");
 
   ADD_ICON (bundled_by_full_filename, ".editorconfig", "format-indent-more-symbolic");
   ADD_ICON (bundled_by_full_filename, ".gitignore", "builder-vcs-git-symbolic");