On a CL with a single file, presubmit writes all this noise:

Running /b/build/slave/linux/build/src/PRESUBMIT.py
DEBUG:root:Running CheckChangeOnCommit in /b/build/slave/linux/build/src/PRESUBMIT.py
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.(cc|cpp|cxx|mm)$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:git diff -p --no-color --no-prefix --no-ext-diff 691e0c7d46341465de7a605b5f2aee941ccfedc0...HEAD --no-renames;  cwd=/b/build/slave/linux/build/src
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:/usr/bin/python /b/build/slave/linux/build/src/tools/checkperms/checkperms.py --root /b/build/slave/linux/build/src --file content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:^(android_webview|base|content|net)[\\\/].* matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.(cc|cpp|cxx|mm)$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:LocalPaths: ['content/browser/gpu/gpu_data_manager_impl_private.cc']
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.(cc|cpp|cxx|mm)$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:.+\.cc$ matched content/browser/gpu/gpu_data_manager_impl_private.cc
DEBUG:root:Running CheckChangeOnCommit done.

The "a matched b" lines are boring and numerous, so remove this log line.
If we ever need it to debug something, we can add it back then (temporarily).

(From https://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presubmit/builds/260304/steps/presubmit/logs/stdio)

BUG=none

Review-Url: https://codereview.chromium.org/2341103002