Ensure generator fallbacks work even when a context is given.

Signed-off-by: Yehuda Katz <wycats@Yehuda-Katz.local>

railties/lib/rails/generators.rb

@@ -198,7 +198,7 @@ def self.find_by_namespace(name, base=nil, context=nil) #:nodoc:
         return klass if klass
       end
 
-      invoke_fallbacks_for(name, base)
+      invoke_fallbacks_for(name, base) || invoke_fallbacks_for(context, name)
     end
 
     # Receives a namespace, arguments and the behavior to invoke the generator.

railties/test/generators_test.rb

@@ -150,6 +150,13 @@ def test_fallbacks_for_generators_on_find_by_namespace
     assert_equal "test_unit:generators:plugin", klass.namespace
   end
 
+  def test_fallbacks_for_generators_on_find_by_namespace_with_context
+    Rails::Generators.fallbacks[:remarkable] = :test_unit
+    klass = Rails::Generators.find_by_namespace(:remarkable, :rails, :plugin)
+    assert klass
+    assert_equal "test_unit:generators:plugin", klass.namespace
+  end
+
   def test_fallbacks_for_generators_on_invoke
     Rails::Generators.fallbacks[:shoulda] = :test_unit
     TestUnit::Generators::ModelGenerator.expects(:start).with(["Account"], {})