MD WebUI: Explicitly set text color in cr-action-menu

ui/webui/resources/cr_elements/cr_action_menu/cr_action_menu.html

Index: ui/webui/resources/cr_elements/cr_action_menu/cr_action_menu.html
diff --git a/ui/webui/resources/cr_elements/cr_action_menu/cr_action_menu.html b/ui/webui/resources/cr_elements/cr_action_menu/cr_action_menu.html
index f2fa45e52b1c2fe4a27d31ffc4b3d54aaaa4e68e..d40683f858504ac833b48664286c7320c6cd7c42 100644
--- a/ui/webui/resources/cr_elements/cr_action_menu/cr_action_menu.html
+++ b/ui/webui/resources/cr_elements/cr_action_menu/cr_action_menu.html
@@ -9,7 +9,6 @@
         background-color: white;
         border: none;
         box-shadow: 0 2px 6px var(--paper-grey-500);
-        color: inherit;
         margin: 0;
         outline: none;
         padding: 8px 0;
@@ -23,7 +22,7 @@
         background: none;
         border: none;
         box-sizing: border-box;
-        color: inherit;
+        color: var(--paper-grey-900);

[tsergeant, 2017/04/07 01:53:10]

I guess this could also be fixed by changing the individual usage sites, but
going back to this seems safer and easier.

Also note that this has changed from grey-800 to grey-900, which AFAIK is the
new correct color.

         font: inherit;
         min-height: 32px;
         padding: 0 24px;