Revert of [gn] Switch win clang bot to gn (patchset #1 id:1 of...

Revert of [gn] Switch win clang bot to gn (patchset #1 id:1 of https://codereview.chromium.org/2310863002/ )

Reason for revert:
Fails compilation:
https://build.chromium.org/p/client.v8/builders/V8%20Win64%20-%20clang

Original issue's description:
> [gn] Switch win clang bot to gn
>
> BUG=chromium:474921
> NOTRY=true
>
> Committed: https://crrev.com/1740587772bbd1ffb7b79a90deb16519e8d47588
> Cr-Commit-Position: refs/heads/master@{#39156}

TBR=jochen@chromium.org,vogelheim@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:474921

Review-Url: https://codereview.chromium.org/2311853002
Cr-Commit-Position: refs/heads/master@{#39158}

infra/mb/mb_config.pyl

@@ -52,7 +52,7 @@
         'gn_release_x86_no_snap_shared_minimal_symbols',
       'V8 Win64': 'gn_release_x64_minimal_symbols',
       'V8 Win64 - debug': 'gn_debug_x64_minimal_symbols',
-      'V8 Win64 - clang': 'gn_release_x64_clang',
+      'V8 Win64 - clang': 'gyp_release_x64_clang',
       # Mac.
       'V8 Mac': 'gn_release_x86',
       'V8 Mac - debug': 'gn_debug_x86',
@@ -249,8 +249,6 @@
     # GN release configs for x64.
     'gn_release_x64': [
       'gn', 'release_bot', 'x64', 'swarming'],
-    'gn_release_x64_clang': [
-      'gn', 'release_bot', 'x64', 'clang', 'swarming'],
     'gn_release_x64_internal': [
       'gn', 'release_bot', 'x64', 'swarming', 'v8_snapshot_internal'],
     'gn_release_x64_minimal_symbols': [
@@ -385,6 +383,8 @@
       'v8_verify_heap'],
     'gyp_release_x64_cfi_symbolized': [
       'gyp', 'release_bot', 'x64', 'cfi', 'swarming', 'symbolized'],
+    'gyp_release_x64_clang': [
+      'gyp', 'release_bot', 'x64', 'clang', 'swarming'],
     'gyp_release_x64_gcc_coverage': [
       'gyp', 'release_bot', 'x64', 'coverage', 'gcc'],