rm broken bundle update task & defunct custom RubyGem caching scheme

[skip sauce]

.travis.yml

@@ -7,7 +7,6 @@ node_js:
 before_install:
   - travis_retry pip install -r test-infra/requirements.txt --user
   - rvm install 2.0.0 && rvm use 2.0.0
-  - export GEMDIR=$(rvm gemdir)
   - "export TRAVIS_COMMIT_MSG=\"$(git log --format=%B --no-merges -n 1)\""
   - echo "$TRAVIS_COMMIT_MSG" | grep '\[skip validator\]'; export TWBS_DO_VALIDATOR=$?; true
   - echo "$TRAVIS_COMMIT_MSG" | grep '\[skip sauce\]'; export TWBS_DO_SAUCE=$?; true

Gruntfile.js

@@ -399,14 +399,6 @@ module.exports = function (grunt) {
     exec: {
       npmUpdate: {
         command: 'npm update'
-      },
-      bundleUpdate: {
-        command: function () {
-          // Update dev gems and all the test gemsets
-          return 'bundle update && ' + glob.sync('test-infra/gemfiles/*.gemfile').map(function (gemfile) {
-            return 'BUNDLE_GEMFILE=' + gemfile + ' bundle update';
-          }).join(' && ');
-        }
       }
     },
 
@@ -531,7 +523,4 @@ module.exports = function (grunt) {
       done();
     });
   });
-  // Task for updating the cached RubyGem packages used by the Travis build (which are controlled by test-infra/Gemfile.lock).
-  // This task should be run and the updated file should be committed whenever Bootstrap's RubyGem dependencies change.
-  grunt.registerTask('update-gemfile-lock', ['exec:bundleUpdate']);
 };

test-infra/README.md

@@ -13,16 +13,13 @@ Similar to git, `s3_cache.py` makes the assumption that [SHA-256 will effectivel
 
 
 ### For Bootstrap specifically
-`s3_cache.py` is used to cache the npm packages that our Grunt tasks depend on and the RubyGems that Jekyll depends on. (Jekyll is needed to compile our docs to HTML so that we can run them thru an HTML5 validator.)
+`s3_cache.py` is used to cache the npm packages that our Grunt tasks depend on.
 
 For npm, the `node_modules` directory is cached based on our `npm-shrinkwrap.json` file.
 
-For RubyGems, the `gemdir` of the current RVM-selected Ruby is cached based on the `pseudo_Gemfile.lock` file generated by our Travis build script.
-`pseudo_Gemfile.lock` contains the versions of Ruby and Jekyll that we're using (read our `.travis.yml` for details).
-
 
 ## Why is `s3_cache.py` necessary?
-`s3_cache.py` is used to speed up Bootstrap's Travis builds. Installing npm packages and RubyGems used to take up a significant fraction of our total build times. Also, at the time that `s3_cache.py` was written, npm was occasionally unreliable.
+`s3_cache.py` is used to speed up Bootstrap's Travis builds. Installing npm packages used to take up a significant fraction of our total build times. Also, at the time that `s3_cache.py` was written, npm was occasionally unreliable.
 
 Travis does offer built-in caching on their paid plans, but this do-it-ourselves S3 solution is significantly cheaper since we only need caching and not Travis' other paid features.
 

test-infra/S3Cachefile.json

@@ -3,10 +3,5 @@
         "key": "./npm-shrinkwrap.json",
         "cache": "../node_modules",
         "generate": "./uncached-npm-install.sh"
-    },
-    "rubygems": {
-        "key": "$BUNDLE_GEMFILE",
-        "cache": "../vendor/cache",
-        "generate": "cd .. ; bundle install --path=\"`pwd`/vendor/cache\""
     }
 }

test-infra/gemfiles/core.gemfile

-# Ruby Gems for the 'core' set of tests
-# Run `grunt update-gemfile-lock` to update to the latest compatible versions
-
-source 'https://rubygems.org'
-
-gem 'sass', '~> 3.4.9'
-gem 'scss-lint', '~> 0.31'

test-infra/gemfiles/core.gemfile.lock

-GEM
-  remote: https://rubygems.org/
-  specs:
-    rainbow (2.0.0)
-    sass (3.4.9)
-    scss-lint (0.31.0)
-      rainbow (~> 2.0)
-      sass (~> 3.4.1)
-
-PLATFORMS
-  ruby
-
-DEPENDENCIES
-  sass (~> 3.4.9)
-  scss-lint (~> 0.31)