fetch: stop specifying .DEPS.git for any repos

None of these repos has had a .DEPS.git file in over 3.5 years.

R=ehmaldonado

Bug: 824734
Change-Id: I768e247eee5a8eff9fcf8f1891497840909ec9fa
Reviewed-on: https://chromium-review.googlesource.com/982521
Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>
Commit-Queue: Aaron Gable <agable@chromium.org>

fetch_configs/chromium.py

@@ -17,7 +17,6 @@ class Chromium(config_util.Config):
     url = 'https://chromium.googlesource.com/chromium/src.git'
     solution = { 'name'   :'src',
                  'url'    : url,
-                 'deps_file': '.DEPS.git',
                  'managed'   : False,
                  'custom_deps': {},
     }

fetch_configs/infra.py

@@ -21,7 +21,6 @@ class Infra(config_util.Config):
           {
             'name'     : 'infra',
             'url'      : 'https://chromium.googlesource.com/infra/infra.git',
-            'deps_file': '.DEPS.git',
             'managed'  : False,
           }
         ],

fetch_configs/infra_internal.py

@@ -22,7 +22,6 @@ class InfraInternal(config_util.Config):
         {
           'name': 'infra_internal',
           'url': url('chrome-internal', 'infra/infra_internal'),
-          'deps_file': '.DEPS.git',
           'managed': False
         },
       ],