fix(tabs,date-picker,theming): restore tabs and date-picker themes

closes #5163, fixes #5141, closes #5164, closes #5155

src/core/services/theming/theming.js

@@ -439,7 +439,10 @@ function parseRules(theme, colorType, rules) {
     // Don't apply a selector rule to the default theme, making it easier to override
     // styles of the base-component
     if (theme.name == 'default') {
-      newRule = newRule.replace(/((\w|\.|-)+)\.md-default-theme((\.|\w|-|:|\(|\)|\[|\]|"|'|=)*)/g, '$&, $1$3');
+      var themeRuleRegex = /((?:(?:(?: |>|\.|\w|-|:|\(|\)|\[|\]|"|'|=)+) )?)((?:(?:\w|\.|-)+)?)\.md-default-theme((?: |>|\.|\w|-|:|\(|\)|\[|\]|"|'|=)*)/g;
+      newRule = newRule.replace(themeRuleRegex, function(match, prefix, target, suffix) {
+        return match + ', ' + prefix + target + suffix;
+      });
     }
     generatedRules.push(newRule);
   });