Looks like the subree mirror of breakpad
(i.e. https://chromium.googlesource.com/breakpad/breakpad into https://chromium.googlesource.com/breakpad/breakpad/src.git/+log/master?n=200)
ended up bringin the subree (the latter project) in a broken state.

Look at https://chromium.googlesource.com/breakpad/breakpad/src.git/+log/master?n=200
it seems that a part of the history has been replayed.

The history in the authoritative repo looks, good, e.g. the last 3 entries are:
8915f7b Don't merge the mappings if their exec bit are different. by Primiano Tucci · 14 hours ago master
4d69050 Add an optional root prefix to Linux dumpers by Dominik Laskowski · 21 hours ago
f3d28e9 Handle multiple microdumps in system log. by Maria Mandlis · 11 days ago

However in the subtree repo a part of the history seems to have been repeated twice:
a1fd372 Don't merge the mappings if their exec bit are different. by Primiano Tucci · 14 hours ago master
58a03f9 Add an optional root prefix to Linux dumpers by Dominik Laskowski · 21 hours ago
79ff11b Handle multiple microdumps in system log. by Maria Mandlis · 11 days ago
785f863 Support processing microdumps for x86 architecture. by Maria Mandlis · 3 weeks ago
58cba0f Try loading msdiaNNN.dll if CoCreateInstance(CLSID_DiaSource) fails by Birunthan Mohanathas · 3 weeks ago
...and then again...
a089d5e Handle multiple microdumps in system log. by Maria Mandlis · 11 days ago master-large-syms
1ace242 Support processing microdumps for x86 architecture. by Maria Mandlis · 3 weeks ago
dfa3885 Try loading msdiaNNN.dll if CoCreateInstance(CLSID_DiaSource) fails by Birunthan Mohanathas · 3 weeks ago



How did that happen? more importantly, can we cleanup and re-mirror?
Fortunately we didn't roll the broken history in chrome yet. I happen to realize this by paranoidically eyeballing a DEPS roll in https://codereview.chromium.org/1773943003/.