[build] Add MB config for deprecation warning bot

TBR=yangguo@chromium.org
NOTRY=true

Bug: v8:7963
Change-Id: I1a91047b2a3c7d128f3b01a0970ce53a63c196d6
Reviewed-on: https://chromium-review.googlesource.com/1145187Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54585}

infra/mb/mb_config.pyl

@@ -73,6 +73,7 @@
       'V8 Linux64 - debug builder': 'debug_x64',
       'V8 Linux64 - custom snapshot - debug builder': 'debug_x64_custom',
       'V8 Linux64 - internal snapshot': 'release_x64_internal',
+      'V8 Linux64 - debug - deprecation warnings': 'debug_x64_deprecation_warnings',
       'V8 Linux64 - verify csa': 'release_x64_verify_csa',
       # Jumbo.
       'V8 Linux64 Jumbo': 'release_x64_jumbo',
@@ -502,6 +503,8 @@
       'x64', 'asan', 'edge'],
     'debug_x64_custom': [
       'debug_bot', 'x64', 'v8_snapshot_custom'],
+    'debug_x64_deprecation_warnings': [
+      'debug_bot', 'x64', 'v8_imminent_deprecation_warnings'],
     'debug_x64_fuchsia': [
       'debug_bot', 'x64', 'fuchsia'],
     'debug_x64_gcc': [
@@ -833,6 +836,10 @@
       'gn_args': 'v8_optimized_debug=false',
     },
 
+    'v8_imminent_deprecation_warnings': {
+      'gn_args': 'v8_imminent_deprecation_warnings=true',
+    },
+
     'v8_interpreted_regexp': {
       'gn_args': 'v8_interpreted_regexp=true',
     },