Bind content type text/x-h to clike mode

Change-Id: I37454147759bbfbcb268690dd8f00ad6bf4a8b32
diff --git a/gerrit-gwtui/src/main/java/net/codemirror/mode/mode_map b/gerrit-gwtui/src/main/java/net/codemirror/mode/mode_map
index e448fa9..ede7714 100644
--- a/gerrit-gwtui/src/main/java/net/codemirror/mode/mode_map
+++ b/gerrit-gwtui/src/main/java/net/codemirror/mode/mode_map
@@ -1,6 +1,7 @@
 clike:
-text/x-csrc
 text/x-c
+text/x-h
+text/x-csrc
 text/x-chdr
 text/x-c++src
 text/x-c++hdr