tombstoned: fix file creation for ANRs.

Bug: http://b/188315622
Test: manual
Change-Id: I2948b929beb3093b59c8d37b706c857e7422a3cc
Merged-In: I2948b929beb3093b59c8d37b706c857e7422a3cc
(cherry picked from commit 931274862fc55bc723ee72c0c989984c4ffb7776)
1 file changed