Refactor how we fetch Telemetry deps conditionally

DEPS

 # This file is used to manage the dependencies of the Chromium src repo. It is
 # used by gclient to determine what version of each dependency to check out, and
 # where.
 #
 # For more information, please refer to the official documentation:
 #   https://sites.google.com/a/chromium.org/dev/developers/how-tos/get-the-code
 #
 # When adding a new dependency, please update the top-level .gitignore file
 # to list the dependency's destination directory.
 #
@@ skipping 872 matching lines @@
                 '--bucket', 'chromium-nodejs',
                 '-s', 'src/third_party/node/node_modules.tar.gz.sha1',
     ],
   },
 
   # Download Telemetry's binary dependencies
   {
     'name': 'fetch_telemetry_binary_dependencies',
     'pattern': '.',
     'action': [ 'python',
+                'src/tools/perf/conditionally_execute',
+                '--gyp-condition', 'fetch_telemetry_dependencies=1',
                 'src/third_party/catapult/telemetry/bin/fetch_telemetry_binary_dependencies',
     ],
   },
 
   # Download checkstyle for use in PRESUBMIT for Java changes.
   # TODO(jbudorick): Move this back down to the android section of hooks_os
   # once it's no longer necessary for the chromium_presubmit bot.
   {
     'name': 'checkstyle',
     'pattern': '.',
@@ skipping 277 matching lines @@
 }
 
 recursedeps = [
   # buildtools provides clang_format, libc++, and libc++abi
   'src/buildtools',
   # android_tools manages the NDK.
   'src/third_party/android_tools',
   # ANGLE manages DEPS that it also owns the build files for, such as dEQP.
   ("src/third_party/angle", "DEPS.chromium"),
 ]