Pin depot_tools version in DEPS to prevent breakages

DEPS

 # This file contains dependencies for WebRTC.
 
 vars = {
   'chromium_git': 'https://chromium.googlesource.com',
   'chromium_revision': '1236993289b3a34ac29c6d18fbd31273eee86c73',
   'boringssl_git': 'https://boringssl.googlesource.com',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling swarming_client
   # and whatever else without interference from each other.
   'swarming_revision': 'a56c2b39ca23bdf41458421a7f825ddbf3f43f28',
@@ skipping 30 matching lines @@
   'src/testing':
     Var('chromium_git') + '/chromium/src/testing' + '@' + '8aa4104160f1437425ef3679b21fc7ef4c231ae1',
   'src/third_party':
     Var('chromium_git') + '/chromium/src/third_party' + '@' + '578852cd3e31022029ddd0edd18f86d000de1454',
   'src/third_party/boringssl/src':
    Var('boringssl_git') + '/boringssl.git' + '@' +  Var('boringssl_revision'),
   'src/third_party/catapult':
    Var('chromium_git') + '/external/github.com/catapult-project/catapult.git' + '@' + Var('catapult_revision'),
   'src/third_party/colorama/src':
     Var('chromium_git') + '/external/colorama.git' + '@' + '799604a1041e9b3bc5d2789ecbd7e8db2e18e6b8',
+  'src/third_party/depot_tools':
+    Var('chromium_git') + '/chromium/tools/depot_tools.git' + '@' + '6d0d04458d9c345bc7d77681996d89d6e5fc742c',
   'src/third_party/ffmpeg':
     Var('chromium_git') + '/chromium/third_party/ffmpeg.git' + '@' + '97ebed67951a157f6add59046024bff5fa20f4ae',
   'src/third_party/googletest/src':
     Var('chromium_git') + '/external/github.com/google/googletest.git' + '@' + '42bc671f47b122fad36db5eccbc06868afdf7862',
   'src/third_party/jsoncpp/source':
     Var('chromium_git') + '/external/github.com/open-source-parsers/jsoncpp.git' + '@' + 'f572e8e42e22cfcf5ab0aea26574f408943edfa4', # from svn 248
   # Used for building libFuzzers (only supports Linux).
   'src/third_party/libFuzzer/src':
     Var('chromium_git') + '/chromium/llvm-project/llvm/lib/Fuzzer.git' + '@' +  Var('libfuzzer_revision'),
   'src/third_party/libjpeg_turbo':
@@ skipping 98 matching lines @@
     'pattern': '.',
     'action': [
         'python',
         'src/build/landmines.py',
         '--landmine-scripts',
         'src/tools_webrtc/get_landmines.py',
         '--src-dir',
         'src',
     ],
   },
+  {
+    # Ensure that the DEPS'd "depot_tools" has its self-update capability
+    # disabled.
+    'name': 'disable_depot_tools_selfupdate',
+    'pattern': '.',
+    'action': [
+        'python',
+        'src/third_party/depot_tools/update_depot_tools_toggle.py',
+        '--disable',
+    ],
+  },
   # Android dependencies. Many are downloaded using Google Storage these days.
   # They're copied from https://cs.chromium.org/chromium/src/DEPS for all
   # such dependencies we share with Chromium.
   {
     # This downloads SDK extras and puts them in the
     # third_party/android_tools/sdk/extras directory.
     'name': 'sdkextras',
     'pattern': '.',
     # When adding a new sdk extras package to download, add the package
     # directory and zip file to .gitignore in third_party/android_tools.
@@ skipping 337 matching lines @@
                '--bucket', 'chromium-webrtc-resources',
                'src/resources'],
   },
 ]
 recursedeps = [
   # buildtools provides clang_format, libc++, and libc++abi.
   'src/buildtools',
   # android_tools manages the NDK.
   'src/third_party/android_tools',
 ]