Only add resources and frameworks build phase when needed

This changes the project integrator to only add build phases to the
user's project if there are resources of frameworks that will be copied
in that phase.

lib/cocoapods/installer/user_project_integrator/target_integrator.rb

@@ -303,9 +303,9 @@ module Pod
                 output_extension = TargetIntegrator.output_extension_for_resource(File.extname(input_path))
                 File.join(base_path, File.basename(input_path, File.extname(input_path)) + output_extension)
               end.uniq
+              TargetIntegrator.validate_input_output_path_limit(input_paths, output_paths)
+              TargetIntegrator.create_or_update_copy_resources_script_phase_to_target(native_target, script_path, input_paths, output_paths)
             end
-            TargetIntegrator.validate_input_output_path_limit(input_paths, output_paths)
-            TargetIntegrator.create_or_update_copy_resources_script_phase_to_target(native_target, script_path, input_paths, output_paths)
           end
         end
 
@@ -337,9 +337,9 @@ module Pod
             unless framework_paths_by_config.all?(&:empty?)
               input_paths = [target.embed_frameworks_script_relative_path, *framework_paths_by_config.map { |fw| [fw[:input_path], fw[:dsym_input_path]] }.flatten.compact]
               output_paths = framework_paths_by_config.map { |fw| [fw[:output_path], fw[:dsym_output_path]] }.flatten.compact.uniq
+              TargetIntegrator.validate_input_output_path_limit(input_paths, output_paths)
+              TargetIntegrator.create_or_update_embed_frameworks_script_phase_to_target(native_target, script_path, input_paths, output_paths)
             end
-            TargetIntegrator.validate_input_output_path_limit(input_paths, output_paths)
-            TargetIntegrator.create_or_update_embed_frameworks_script_phase_to_target(native_target, script_path, input_paths, output_paths)
           end
         end