simpleperf: fix build id check of files in symfs.
In dso.cpp, build_id_map_ should use path_ instead of GetAccessiblePath() as the key.
However, patch https://android-review.googlesource.com/#/c/175654/ wrongly used
GetAccessiblePath() as the key in build_id_map_. This patch fixes the error and add
corresponding test.
Check if file in symfs exists before using it as debug file path.
If the build id of debug file path doesn't match the one in build_id_map_, output
warning to user.
Bug: 28911532
Test: run simpleperf_unit_test.
Change-Id: I21bca508359a492245db4cba5d287005363cd465
9 files changed
