brew-pull: Clarify comment concerning whitespace

Library/Contributions/examples/brew-pull.rb

@@ -36,9 +36,10 @@ HOMEBREW_REPOSITORY.cd do
     # Store current revision
     revision = `git log -n1 --format=%H`.strip()
 
-    # Makes sense to squash whitespace errors, we don't want them.
     ohai 'Applying patch'
     patch_args = %w[am --signoff]
+    # Normally we don't want whitespace errors, but squashing them can break
+    # patches so an option is provided to skip this step.
     patch_args << '--whitespace=fix' unless ARGV.include? '--ignore-whitespace'
     patch_args << patchpath