we already do this (?)

It actually isn't on by default, you need to set strip_absolute_paths_from_debug_symbols=true.

This is for either changing the default or changing the bots to use this.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/050dbe550d14e99ad4e83093d4f4e79642b9edc3

commit 050dbe550d14e99ad4e83093d4f4e79642b9edc3
Author: dpranke <dpranke@chromium.org>
Date: Thu Apr 27 03:58:25 2017

Ensure that builders that use goma strip absolute paths by default.

This CL tweaks the MB configs so that any builder that is using goma
also sets strip_absolute_paths_from_debug_symbols_by_default=true.
This helps ensure that we get the best goma cache hit rate possible.
We don't just make the default equal to use_goma=true because doing
so may make it harder for devs to debug binaries, and we want devs
to be able to both debug binaries and use goma by default; the
tradeoff is that their builds are slightly slower.

R=thakis@chromium.org, jochen@chromium.org
BUG=603286,  712790 

Review-Url: https://codereview.chromium.org/2837863005
Cr-Commit-Position: refs/heads/master@{#467574}

[modify] https://crrev.com/050dbe550d14e99ad4e83093d4f4e79642b9edc3/build/config/compiler/BUILD.gn
[modify] https://crrev.com/050dbe550d14e99ad4e83093d4f4e79642b9edc3/tools/mb/mb_config.pyl

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/999471957dc5cf51048b0b344c58925a2954d452

commit 999471957dc5cf51048b0b344c58925a2954d452
Author: dpranke <dpranke@chromium.org>
Date: Thu Apr 27 20:32:33 2017

Revert of Ensure that builders that use goma strip absolute paths by default. (patchset #1 id:1 of https://codereview.chromium.org/2837863005/ )

Reason for revert:
Reverting in case this is related to the goma errors in https://crbug.com/716089

Original issue's description:
> Ensure that builders that use goma strip absolute paths by default.
>
> This CL tweaks the MB configs so that any builder that is using goma
> also sets strip_absolute_paths_from_debug_symbols_by_default=true.
> This helps ensure that we get the best goma cache hit rate possible.
> We don't just make the default equal to use_goma=true because doing
> so may make it harder for devs to debug binaries, and we want devs
> to be able to both debug binaries and use goma by default; the
> tradeoff is that their builds are slightly slower.
>
> R=thakis@chromium.org, jochen@chromium.org
> BUG=603286,  712790 
>
> Review-Url: https://codereview.chromium.org/2837863005
> Cr-Commit-Position: refs/heads/master@{#467574}
> Committed: https://chromium.googlesource.com/chromium/src/+/050dbe550d14e99ad4e83093d4f4e79642b9edc3

TBR=jochen@chromium.org,thakis@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=603286,  712790 

Review-Url: https://codereview.chromium.org/2843403004
Cr-Commit-Position: refs/heads/master@{#467769}

[modify] https://crrev.com/999471957dc5cf51048b0b344c58925a2954d452/build/config/compiler/BUILD.gn
[modify] https://crrev.com/999471957dc5cf51048b0b344c58925a2954d452/tools/mb/mb_config.pyl

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c7b0cf640eee349516d275dad1a00bd393ac8644

commit c7b0cf640eee349516d275dad1a00bd393ac8644
Author: dpranke <dpranke@chromium.org>
Date: Tue May 09 17:36:27 2017

Reland of Ensure that builders that use goma strip absolute paths by default. (patchset #1 id:1 of https://codereview.chromium.org/2843403004/ )

Reason for revert:
Relanding, since this was not a cause of the goma outage.

Original issue's description:
> Revert of Ensure that builders that use goma strip absolute paths by default. (patchset #1 id:1 of https://codereview.chromium.org/2837863005/ )
>
> Reason for revert:
> Reverting in case this is related to the goma errors in https://crbug.com/716089
>
> Original issue's description:
> > Ensure that builders that use goma strip absolute paths by default.
> >
> > This CL tweaks the MB configs so that any builder that is using goma
> > also sets strip_absolute_paths_from_debug_symbols_by_default=true.
> > This helps ensure that we get the best goma cache hit rate possible.
> > We don't just make the default equal to use_goma=true because doing
> > so may make it harder for devs to debug binaries, and we want devs
> > to be able to both debug binaries and use goma by default; the
> > tradeoff is that their builds are slightly slower.
> >
> > R=thakis@chromium.org, jochen@chromium.org
> > BUG=603286,  712790 
> >
> > Review-Url: https://codereview.chromium.org/2837863005
> > Cr-Commit-Position: refs/heads/master@{#467574}
> > Committed: https://chromium.googlesource.com/chromium/src/+/050dbe550d14e99ad4e83093d4f4e79642b9edc3
>
> TBR=jochen@chromium.org,thakis@chromium.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=603286,  712790 
>
> Review-Url: https://codereview.chromium.org/2843403004
> Cr-Commit-Position: refs/heads/master@{#467769}
> Committed: https://chromium.googlesource.com/chromium/src/+/999471957dc5cf51048b0b344c58925a2954d452

TBR=jochen@chromium.org,thakis@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=603286,  712790 

Review-Url: https://codereview.chromium.org/2873513003
Cr-Commit-Position: refs/heads/master@{#470369}

[modify] https://crrev.com/c7b0cf640eee349516d275dad1a00bd393ac8644/build/config/compiler/BUILD.gn
[modify] https://crrev.com/c7b0cf640eee349516d275dad1a00bd393ac8644/tools/mb/mb_config.pyl

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/67970ee192706eed7c080811732bab47383d636c

commit 67970ee192706eed7c080811732bab47383d636c
Author: dpranke <dpranke@chromium.org>
Date: Wed May 10 00:36:40 2017

Revert of Ensure that builders that use goma strip absolute paths by default. (patchset #1 id:1 of https://codereview.chromium.org/2873513003/ )

Reason for revert:
Speculatively reverting in case this is causing goma crashes (see crbug.com/720074)

Original issue's description:
> Reland of Ensure that builders that use goma strip absolute paths by default. (patchset #1 id:1 of https://codereview.chromium.org/2843403004/ )
>
> Reason for revert:
> Relanding, since this was not a cause of the goma outage.
>
> Original issue's description:
> > Revert of Ensure that builders that use goma strip absolute paths by default. (patchset #1 id:1 of https://codereview.chromium.org/2837863005/ )
> >
> > Reason for revert:
> > Reverting in case this is related to the goma errors in https://crbug.com/716089
> >
> > Original issue's description:
> > > Ensure that builders that use goma strip absolute paths by default.
> > >
> > > This CL tweaks the MB configs so that any builder that is using goma
> > > also sets strip_absolute_paths_from_debug_symbols_by_default=true.
> > > This helps ensure that we get the best goma cache hit rate possible.
> > > We don't just make the default equal to use_goma=true because doing
> > > so may make it harder for devs to debug binaries, and we want devs
> > > to be able to both debug binaries and use goma by default; the
> > > tradeoff is that their builds are slightly slower.
> > >
> > > R=thakis@chromium.org, jochen@chromium.org
> > > BUG=603286,  712790 
> > >
> > > Review-Url: https://codereview.chromium.org/2837863005
> > > Cr-Commit-Position: refs/heads/master@{#467574}
> > > Committed: https://chromium.googlesource.com/chromium/src/+/050dbe550d14e99ad4e83093d4f4e79642b9edc3
> >
> > TBR=jochen@chromium.org,thakis@chromium.org
> > # Skipping CQ checks because original CL landed less than 1 days ago.
> > NOPRESUBMIT=true
> > NOTREECHECKS=true
> > NOTRY=true
> > BUG=603286,  712790 
> >
> > Review-Url: https://codereview.chromium.org/2843403004
> > Cr-Commit-Position: refs/heads/master@{#467769}
> > Committed: https://chromium.googlesource.com/chromium/src/+/999471957dc5cf51048b0b344c58925a2954d452
>
> TBR=jochen@chromium.org,thakis@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=603286,  712790 
>
> Review-Url: https://codereview.chromium.org/2873513003
> Cr-Commit-Position: refs/heads/master@{#470369}
> Committed: https://chromium.googlesource.com/chromium/src/+/c7b0cf640eee349516d275dad1a00bd393ac8644

TBR=jochen@chromium.org,thakis@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=603286,  712790 

Review-Url: https://codereview.chromium.org/2874613002
Cr-Commit-Position: refs/heads/master@{#470444}

[modify] https://crrev.com/67970ee192706eed7c080811732bab47383d636c/build/config/compiler/BUILD.gn
[modify] https://crrev.com/67970ee192706eed7c080811732bab47383d636c/tools/mb/mb_config.pyl

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b1c56e14102683640d1cd69bcfac692875893fc6

commit b1c56e14102683640d1cd69bcfac692875893fc6
Author: dpranke <dpranke@chromium.org>
Date: Thu May 25 20:47:58 2017

Reland of Ensure that builders that use goma strip absolute paths by default. (patchset #1 id:1 of https://codereview.chromium.org/2874613002/ )

Reason for revert:
Reland #3 ...

Original issue's description:
> Revert of Ensure that builders that use goma strip absolute paths by default. (patchset #1 id:1 of https://codereview.chromium.org/2873513003/ )
>
> Reason for revert:
> Speculatively reverting in case this is causing goma crashes (see crbug.com/720074)
>
> Original issue's description:
> > Reland of Ensure that builders that use goma strip absolute paths by default. (patchset #1 id:1 of https://codereview.chromium.org/2843403004/ )
> >
> > Reason for revert:
> > Relanding, since this was not a cause of the goma outage.
> >
> > Original issue's description:
> > > Revert of Ensure that builders that use goma strip absolute paths by default. (patchset #1 id:1 of https://codereview.chromium.org/2837863005/ )
> > >
> > > Reason for revert:
> > > Reverting in case this is related to the goma errors in https://crbug.com/716089
> > >
> > > Original issue's description:
> > > > Ensure that builders that use goma strip absolute paths by default.
> > > >
> > > > This CL tweaks the MB configs so that any builder that is using goma
> > > > also sets strip_absolute_paths_from_debug_symbols_by_default=true.
> > > > This helps ensure that we get the best goma cache hit rate possible.
> > > > We don't just make the default equal to use_goma=true because doing
> > > > so may make it harder for devs to debug binaries, and we want devs
> > > > to be able to both debug binaries and use goma by default; the
> > > > tradeoff is that their builds are slightly slower.
> > > >
> > > > R=thakis@chromium.org, jochen@chromium.org
> > > > BUG=603286,  712790 
> > > >
> > > > Review-Url: https://codereview.chromium.org/2837863005
> > > > Cr-Commit-Position: refs/heads/master@{#467574}
> > > > Committed: https://chromium.googlesource.com/chromium/src/+/050dbe550d14e99ad4e83093d4f4e79642b9edc3
> > >
> > > TBR=jochen@chromium.org,thakis@chromium.org
> > > # Skipping CQ checks because original CL landed less than 1 days ago.
> > > NOPRESUBMIT=true
> > > NOTREECHECKS=true
> > > NOTRY=true
> > > BUG=603286,  712790 
> > >
> > > Review-Url: https://codereview.chromium.org/2843403004
> > > Cr-Commit-Position: refs/heads/master@{#467769}
> > > Committed: https://chromium.googlesource.com/chromium/src/+/999471957dc5cf51048b0b344c58925a2954d452
> >
> > TBR=jochen@chromium.org,thakis@chromium.org
> > # Not skipping CQ checks because original CL landed more than 1 days ago.
> > BUG=603286,  712790 
> >
> > Review-Url: https://codereview.chromium.org/2873513003
> > Cr-Commit-Position: refs/heads/master@{#470369}
> > Committed: https://chromium.googlesource.com/chromium/src/+/c7b0cf640eee349516d275dad1a00bd393ac8644
>
> TBR=jochen@chromium.org,thakis@chromium.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=603286,  712790 
>
> Review-Url: https://codereview.chromium.org/2874613002
> Cr-Commit-Position: refs/heads/master@{#470444}
> Committed: https://chromium.googlesource.com/chromium/src/+/67970ee192706eed7c080811732bab47383d636c

TBR=jochen@chromium.org,thakis@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=603286,  712790 

Review-Url: https://codereview.chromium.org/2909523002
Cr-Commit-Position: refs/heads/master@{#474794}

[modify] https://crrev.com/b1c56e14102683640d1cd69bcfac692875893fc6/build/config/compiler/BUILD.gn
[modify] https://crrev.com/b1c56e14102683640d1cd69bcfac692875893fc6/tools/mb/mb_config.pyl