Remove unused variables in root DEPS

DEPS

 # This file is automatically processed to create .DEPS.git which is the file
 # that gclient uses under git.
 #
 # See http://code.google.com/p/chromium/wiki/UsingGit
 #
 # To test manually, run:
 #   python tools/deps2git/deps2git.py -o .DEPS.git -w <gclientdir>
 # where <gcliendir> is the absolute path to the directory containing the
 # .gclient file (the parent of 'src').
 #
 # Then commit .DEPS.git locally (gclient doesn't like dirty trees) and run
 #   gclient sync
 # Verify the thing happened you wanted. Then revert your .DEPS.git change
 # DO NOT CHECK IN CHANGES TO .DEPS.git upstream. It will be automatically
 # updated by a bot when you modify this one.
 #
 # When adding a new dependency, please update the top-level .gitignore file
 # to list the dependency's destination directory.
 
 vars = {
-  # Use this googlecode_url variable only if there is an internal mirror for it.
-  # If you do not know, use the full path while defining your new deps entry.
-  'googlecode_url': 'http://%s.googlecode.com/svn',
-  'sourceforge_url': 'http://svn.code.sf.net/p/%(repo)s/code',
-  'llvm_url': 'http://src.chromium.org/llvm-project',
-  'llvm_git': 'https://llvm.googlesource.com',
+  'chromium_git': 'https://chromium.googlesource.com',
   'libcxx_revision': '48198f9110397fff47fe7c37cbfa296be7d44d3d',
   'libcxxabi_revision': '4ad1009ab3a59fa7a6896d74d5e4de5885697f95',
-  'chromium_git': 'https://chromium.googlesource.com',
-  'skia_git': 'https://skia.googlesource.com',
-  'pdfium_git': 'https://pdfium.googlesource.com',
-  'boringssl_git': 'https://boringssl.googlesource.com',
   'sfntly_revision': '1bdaae8fc788a5ac8936d68bf24f37d977a13dac',
   'skia_revision': '32501a1bd4964576264795ada7e9c3bf572285b3',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling Skia
   # and V8 without interference from each other.
-  'v8_branch': 'trunk',
   'v8_revision': 'bfb312d4b40507780e15bfee2e0dc32f1391c4db', # from svn revision 24925
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling ANGLE
   # and whatever else without interference from each other.
   "angle_revision": "d2f756be4fd198d630b64dc6c3568184363e6d14",
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling build tools
   # and whatever else without interference from each other.
   'buildtools_revision': '56bc51aff4175d3fa27dcd0faa2c345ab046c8a5',
   # Three lines of non-changing comments so that
@@ skipping 241 matching lines @@
     # corresponding .py files have already been deleted.
     'name': 'remove_stale_pyc_files',
     'pattern': 'src/tools/.*\\.py',
     'action': [
         'python',
         'src/tools/remove_stale_pyc_files.py',
         'src/tools',
     ],
   },
 ]