Create a single PodTarget for all subspecs

Group all related specs in the Analyzer.
Make sure to add all FileAccessors for each subspec in the Installer.

lib/cocoapods/installer.rb

@@ -210,11 +210,13 @@ module Pod
     def create_file_accessors
       targets.each do |target|
         target.pod_targets.each do |pod_target|
-          pod_root = sandbox.pod_dir(pod_target.specs.first.root.name)
+          pod_root = sandbox.pod_dir(pod_target.root_spec.name)
           path_list = Sandbox::PathList.new(pod_root)
-          file_accessor = Sandbox::FileAccessor.new(path_list, pod_target.specs.first.consumer(pod_target.platform))
+          file_accessors = pod_target.specs.map do |spec|
+            Sandbox::FileAccessor.new(path_list, spec.consumer(pod_target.platform))
+          end
           pod_target.file_accessors ||= []
-          pod_target.file_accessors << file_accessor
+          pod_target.file_accessors.concat(file_accessors)
         end
       end
     end

lib/cocoapods/installer/analyzer.rb

@@ -182,9 +182,12 @@ module Pod
             target.user_build_configurations = {}
           end
 
-          # TODO group the specs of each Pod
-          specs.each do |spec|
-            pod_target = PodTarget.new([spec], target_definition, sandbox)
+          grouped_specs = specs.map do |spec|
+            specs.select { |s| s.root == spec.root }
+          end.uniq
+
+          grouped_specs.each do |pod_specs|
+            pod_target = PodTarget.new(pod_specs, target_definition, sandbox)
             pod_target.user_build_configurations = target.user_build_configurations
             target.pod_targets << pod_target
           end