Fix reply-to colors in dark mode to increase contrast.

Fixes #7705

src/org/thoughtcrime/securesms/util/ThemeUtil.java

@@ -0,0 +1,25 @@
+package org.thoughtcrime.securesms.util;
+
+import android.content.Context;
+import android.support.annotation.NonNull;
+import android.util.TypedValue;
+
+import org.thoughtcrime.securesms.R;
+
+public class ThemeUtil {
+
+  public static boolean isDarkTheme(@NonNull Context context) {
+    return getAttribute(context, R.attr.theme_type, "light").equals("dark");
+  }
+
+  private static String getAttribute(Context context, int attribute, String defaultValue) {
+    TypedValue outValue = new TypedValue();
+
+    if (context.getTheme().resolveAttribute(attribute, outValue, true)) {
+      return outValue.coerceToString().toString();
+    } else {
+      return defaultValue;
+    }
+  }
+
+}