Revert "automerger: download gn before generating makefiles."

This reverts commit c673dbdbfa853ed101dfc9193a34c14b5134cc78. The downloaded gn is not compatible with the automerger's version of libc; don't attempt to download it.

Change-Id: Ice705f9dc344b7662535f37810701b19e7b08f72
diff --git a/chromium/tools/merge_from_chromium.py b/chromium/tools/merge_from_chromium.py
index a2cdb04..170250a 100755
--- a/chromium/tools/merge_from_chromium.py
+++ b/chromium/tools/merge_from_chromium.py
@@ -259,17 +259,6 @@
   """
   logging.debug('Generating makefiles ...')
 
-  # TODO(torne): come up with a way to deal with hooks from DEPS properly
-  # Download linux GN from google storage as per hook in DEPS.
-  merge_common.GetCommandStdout(['download_from_google_storage',
-                                 '--no_resume',
-                                 '--platform=linux*',
-                                 '--no_auth',
-                                 '--bucket',
-                                 'chromium-gn',
-                                 '-s',
-                                 'tools/gn/bin/linux/gn.sha1'])
-
   # TODO(torne): The .tmp files are generated by
   # third_party/WebKit/Source/WebCore/WebCore.gyp/WebCore.gyp into the source
   # tree. We should avoid this, or at least use a more specific name to avoid