Update DevTools DEPS (trusted)

Rolling build: https://chromium.googlesource.com/chromium/src/build/+log/9fd8acf..b343247

Roll created at https://cr-buildbucket.appspot.com/build/8684365378478627665

Bug: none
Change-Id: I961e67c7570604847fdea2a9f8f679616088d17f
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/7767254
Bot-Commit: Devtools Autoroller <devtools-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: Devtools Autoroller <devtools-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>

Author: devtools-ci-autoroll-builder

DEPS

@@ -12,7 +12,7 @@ vars = {
   'build_with_chromium': False,
 
   'build_url': 'https://chromium.googlesource.com/chromium/src/build.git',
-  'build_revision': '9fd8acf92f5903e357cba3010501392fb47bf211',
+  'build_revision': 'b343247d8a2742e878026a13be01c63141d56b17',
 
   'buildtools_url': 'https://chromium.googlesource.com/chromium/src/buildtools.git',
   'buildtools_revision': '7c8d573b2fcd027a044da24af74ee1a2b446b973',