Change the Rake task dependencies to be less brittle

lib/tasks/requirejs-rails_tasks.rake

@@ -72,17 +72,14 @@ OS X Homebrew users can use 'brew install node'.
   end
 
   namespace :precompile do
-    task all: ["requirejs:precompile:prepare_source",
-               "requirejs:precompile:generate_rjs_driver",
-               "requirejs:precompile:run_rjs",
-               "requirejs:precompile:digestify_and_compress"]
+    task all: ["requirejs:precompile:digestify_and_compress"]
 
     # Invoke another ruby process if we're called from inside
     # assets:precompile so we don't clobber the environment
     #
     # We depend on test_node here so we'll fail early and hard if node
     # isn't available.
-    task external: ["requirejs:test_node"] do
+    task :external do
       ruby_rake_task "requirejs:precompile:all"
     end
 
@@ -132,7 +129,9 @@ OS X Homebrew users can use 'brew install node'.
     end
 
     task run_rjs: ["requirejs:setup",
-                   "requirejs:test_node"] do
+                   "requirejs:test_node",
+                   "requirejs:precompile:prepare_source",
+                   "requirejs:precompile:generate_rjs_driver"] do
       requirejs.config.build_dir.mkpath
       requirejs.config.target_dir.mkpath
       requirejs.config.driver_path.dirname.mkpath
@@ -145,7 +144,7 @@ OS X Homebrew users can use 'brew install node'.
 
     # Copy each built asset, identified by a named module in the
     # build config, to its Sprockets digestified name.
-    task digestify_and_compress: ["requirejs:setup"] do
+    task digestify_and_compress: ["requirejs:precompile:run_rjs"] do
       requirejs.config.build_config["modules"].each do |m|
         module_name = requirejs.config.module_name_for(m)
         paths = requirejs.config.build_config["paths"] || {}