The builder appears to be fine:
https://luci-milo.appspot.com/p/chromium/builders/luci.chromium.ci/android-jumbo-rel

Is your checkout up to date? Have you ran "gclient sync" recently?

Yes and yes, I'm working on fix...

Fix waiting for review: https://chromium-review.googlesource.com/c/chromium/src/+/1327213

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d630de0987d6548a684ad742dad51ff8fb06fa55

commit d630de0987d6548a684ad742dad51ff8fb06fa55
Author: Marcin Wiacek <marcin@mwiacek.com>
Date: Fri Nov 09 07:54:05 2018

Fix Jumbo builds with UNINITIALIZED values

Error:

../../content/browser/service_worker/service_worker_database.h:398:5: error: declaration shadows a variable in namespace 'content::(anonymous)' [-Werror,-Wshadow]
    UNINITIALIZED,
    ^
../../content/browser/service_worker/service_worker_storage.h:566:5: error: declaration shadows a variable in namespace 'content::(anonymous)' [-Werror,-Wshadow]
    UNINITIALIZED,
    ^

./../../content/browser/browser_thread_impl.cc:36:3: note: previous declaration is here
  UNINITIALIZED = 0,
  ^

Example compilation settings:

target_os="android"
target_cpu="arm"
enable_nacl=false
symbol_level=0
remove_webcore_debug_symbols=true
is_debug=false
dcheck_always_on=false
is_component_build=false
use_jumbo_build=true

BUG= 903460 

Change-Id: Ie8c6ef88ac299e02724bcbbeb1db69e67515f62b
Reviewed-on: https://chromium-review.googlesource.com/c/1327213
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Commit-Queue: Marcin Wiącek <marcin@mwiacek.com>
Cr-Commit-Position: refs/heads/master@{#606763}
[modify] https://crrev.com/d630de0987d6548a684ad742dad51ff8fb06fa55/content/browser/service_worker/service_worker_database.cc
[modify] https://crrev.com/d630de0987d6548a684ad742dad51ff8fb06fa55/content/browser/service_worker/service_worker_database.h
[modify] https://crrev.com/d630de0987d6548a684ad742dad51ff8fb06fa55/content/browser/service_worker/service_worker_database_unittest.cc
[modify] https://crrev.com/d630de0987d6548a684ad742dad51ff8fb06fa55/content/browser/service_worker/service_worker_storage.cc
[modify] https://crrev.com/d630de0987d6548a684ad742dad51ff8fb06fa55/content/browser/service_worker/service_worker_storage.h

The CQ jumbo bot runs with goma optimized jumbo chunks (~8 files per translation unit) which is much less than for everyone else (~50 files per translation unit). That makes it miss things. Could be time to look at changing it.

Thanks for taking care of this!

Oh, and the direct trigger was a new clang version with improved checks for shadowed enums. It looks like they have been working for a couple of weeks fixing enough of the source to use the new clang (see  bug 895475 ) but missed a handful of problems in jumbo builds.

Yeah, I think I'm fine with changing the defaults at this point.

We should also double-check the other GN args, to make sure they otherwise exactly match the other configs (e.g., linux-jumbo-rel should otherwise match linux_chromium_rel_ng); otherwise it makes comparing build speeds impossible.

who could take this bug in such case?

I've opened 905588 for this. The particular problem you've fixed so I'm closing it.

Bug 905588 (making it clickable)