Remove cpplint from DEPS

And update tools/lint to use cpplint.py from path.

DEPS was fetchling cpplint from `{chromium_git}/third_party/cpplint/google/styleguide`.

This repo no longer contains cpplint, and now instead is maintained in depot_tools.

The version in depot_tools contains a fix for python3.

Fixed: tint:794
Change-Id: I06c3f8a628ffa3e70887464b1da063b465c05c65
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/50743
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: David Neto <dneto@google.com>
Auto-Submit: Ben Clayton <bclayton@google.com>
Reviewed-by: David Neto <dneto@google.com>

DEPS

@@ -9,7 +9,6 @@ vars = {
   'build_revision': 'c6c4a4c3ae890f2c020a087c90fb8c0b8be2816a',
   'buildtools_revision': 'e3db55b4639f2a331af6f3708ca1fbd22322aac3',
   'clang_revision': 'eb5ab41f3801e2085208204fd71a490573d72dfd',
-  'cpplint_revision': '305ac8725a166ed42e3f5dd3f80d6de2cf840ef1',
   'googletest_revision': '5c8ca58edfb304b2dd5e6061f83387470826dd87',
   'gpuweb_cts_revision': '177a4faf0a7ce6f8c64b42a715c634e363912a74',
   'spirv_headers_revision': 'dafead1765f6c1a5f9f8a76387dcb2abe4e54acd',
@@ -18,9 +17,6 @@ vars = {
 }
 
 deps = {
-  'third_party/cpplint': Var('chromium_git') + Var('github') +
-      '/google/styleguide.git@' + Var('cpplint_revision'),
-
   'third_party/gpuweb-cts': Var('chromium_git') + Var('github') +
       '/gpuweb/cts.git@' + Var('gpuweb_cts_revision'),
 

tools/lint

@@ -18,20 +18,23 @@ ROOT_DIR="$( cd "${SCRIPT_DIR}/.." >/dev/null 2>&1 && pwd )"
 
 set -e  # fail on error
 
-FILTER="-runtime/references"
+if ! command -v cpplint.py &> /dev/null; then
+    echo "cpplint.py not found on PATH"
+    exit 1
+fi
 
+FILTER="-runtime/references"
 FILES="`find src -type f` `find samples -type f`"
 
-if command -v go &> /dev/null
-then
+if command -v go &> /dev/null; then
     # Go is installed. Run cpplint in parallel for speed wins
     go run $SCRIPT_DIR/src/run-parallel/main.go \
          --only-print-failures                  \
-         ./third_party/cpplint/cpplint/cpplint.py \
+         cpplint.py                             \
          --root=$ROOT_DIR                       \
          --filter="$FILTER"                     \
          $ -- $FILES
 else
-    ./third_party/cpplint/cpplint/cpplint.py --root=$ROOT_DIR --filter="$FILTER" $FILES
+    cpplint.py --root=$ROOT_DIR --filter="$FILTER" $FILES
 fi