Handle legacy options in the method_added hook

We only need to process the legacy options at load time, not each time
the class is instantiated, and only when there is an options method
defined.

Library/Homebrew/formula.rb

@@ -37,7 +37,6 @@ class Formula
 
     @active_spec = determine_active_spec(spec)
     validate_attributes :url, :name, :version
-    active_spec.add_legacy_options(options)
     @pkg_version = PkgVersion.new(version, revision)
     @pin = FormulaPin.new(self)
   end
@@ -213,9 +212,6 @@ class Formula
   # tell the user about any caveats regarding this package, return a string
   def caveats; nil end
 
-  # any e.g. configure options for this package
-  def options; [] end
-
   # Deprecated
   DATA = :DATA
   def patches; {} end
@@ -592,6 +588,14 @@ class Formula
       raise "You cannot override Formula#brew in class #{name}"
     when :test
       @test_defined = true
+    when :options
+      instance = allocate
+
+      specs.each do |spec|
+        instance.options.each do |opt, desc|
+          spec.options << Option.new(opt[/^--(.+)$/, 1], desc)
+        end
+      end
     end
   end
 

Library/Homebrew/software_spec.rb

@@ -127,10 +127,6 @@ class SoftwareSpec
       options << Option.new("without-#{name}", "Build without #{name} support")
     end
   end
-
-  def add_legacy_options(list)
-    list.each { |opt, desc| options << Option.new(opt[/^--(.+)$/, 1], desc) }
-  end
 end
 
 class HeadSoftwareSpec < SoftwareSpec