Use ActiveSupport instead of extlib

google-api-client.gemspec

@@ -25,7 +25,7 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency('autoparse', '>= 0.3.3')
   s.add_runtime_dependency('faraday', '>= 0.9.0')
   s.add_runtime_dependency('multi_json', '>= 1.0.0')
-  s.add_runtime_dependency('extlib', '>= 0.9.15')
+  s.add_runtime_dependency('activesupport', '>= 3.2.0')
   s.add_runtime_dependency('jwt', '>= 0.1.5')
   s.add_runtime_dependency('retriable', '~> 1.4')
   s.add_runtime_dependency('launchy', '>= 2.1.1')