[PATCH v1] emacs: make faces clear on dark backgrounds.

[Matt Armstrong <marmstrong@google.com>]

The notmuch-tag-flagged and notmucy-search-flagged-face faces defaulted
to "blue", which is nearly unreadable when a dark background is in use.
This is addressed by using "gold" for dark backgrounds.

There is one remaining unconditional use of "blue" at
notmuch-crypto-part-header, but I don't have any SMIME email, so I'm
unable to see the impact of changing that variable.  I've left it alone.
---
 emacs/notmuch-tag.el | 5 ++++-
 emacs/notmuch.el     | 5 ++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/emacs/notmuch-tag.el b/emacs/notmuch-tag.el
index 1b2ce5c..199582b 100644
--- a/emacs/notmuch-tag.el
+++ b/emacs/notmuch-tag.el
@@ -115,7 +115,10 @@ Used in the default value of `notmuch-tag-formats`."
   :group 'notmuch-faces)
 
 (defface notmuch-tag-flagged
-  '((t :foreground "blue"))
+  '((((class color)
+      (background dark))
+     (:foreground "gold"))
+    (t :foreground "blue"))
   "Face used for the flagged tag.
 
 Used in the default value of `notmuch-tag-formats`."
diff --git a/emacs/notmuch.el b/emacs/notmuch.el
index bd08aa0..9246344 100644
--- a/emacs/notmuch.el
+++ b/emacs/notmuch.el
@@ -313,7 +313,10 @@ there will be called at other points of notmuch execution."
   :group 'notmuch-faces)
 
 (defface notmuch-search-flagged-face
-  '((t
+  '((((class color)
+      (background dark))
+     (:foreground "gold"))
+    (t
      (:foreground "blue")))
   "Face used in search mode face for flagged threads.
 
-- 
2.8.0.rc3.226.g39d4020