Merge pull request #447 from craiglittle/fix-ivar-warning

Silence `@track_files_glob` ivar warning

lib/simplecov.rb

@@ -57,9 +57,9 @@ def start(profile = nil, &block)
     # their coverage to zero.
     #
     def add_not_loaded_files(result)
-      if @track_files_glob
+      if track_files
         result = result.dup
-        Dir[@track_files_glob].each do |file|
+        Dir[track_files].each do |file|
           absolute = File.expand_path(file)
 
           result[absolute] ||= [0] * File.foreach(absolute).count

lib/simplecov/configuration.rb

@@ -47,8 +47,9 @@ def coverage_path
     # or not they were explicitly required. Without this, un-required files
     # will not be present in the final report.
     #
-    def track_files(glob)
-      @track_files_glob = glob
+    def track_files(glob = nil)
+      return @track_files if defined?(@track_files) && glob.nil?
+      @track_files = glob
     end
 
     #