[asan] Exclude non-executable mappings from coverage.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@210649 91177308-0d34-0410-b5e6-96231b3b80d8
[asan] Run Android test with asanwrapper.

This better replicates the target environment.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@210650 91177308-0d34-0410-b5e6-96231b3b80d8
[asan] Fix mmap-ed coverage with coverage=0.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@210655 91177308-0d34-0410-b5e6-96231b3b80d8