Always install xfonts-mathml package if it is available.

build/experimental/install-build-deps.py

Index: build/experimental/install-build-deps.py
diff --git a/build/experimental/install-build-deps.py b/build/experimental/install-build-deps.py
index 52c04f801b9b57dc0474ed1fc45a0a0e4ed293b1..4234bcd2ae4a1c967c749f6ff2394f59e530896d 100755
--- a/build/experimental/install-build-deps.py
+++ b/build/experimental/install-build-deps.py
@@ -363,7 +363,8 @@ def compute_dynamic_package_lists():
 
   if package_exists('fonts-stix'):
     _packages_dev += ('fonts-stix',)

[Daniel Erat, 2016/05/18 22:46:30]

do you mind also removing these fonts-stix references? they were added in error,
as far as i can tell (assuming that no dependencies for a mathml font sneaked in
in the last three months...)

[Vadim Sh., 2016/05/18 22:49:31]

Done.

-  else:
+
+  if package_exists('xfonts-mathml'):
     _packages_dev += ('xfonts-mathml',)
 
   # Some packages are only needed if the distribution actually supports