Remove common/offline-m2

It hasn't been modified for ~2 years, and there are no references to it
in codesearch. So it appears to be leftover from studio's move out of
this branch.

Test: codesearch; treehugger
Change-Id: I2e23a7112e7931c8fbaf5ecc9985fbb2dc50ff4d
221 files changed
tree: 6d9ef1a9448a577395c6386b1ffa08317679e6de
  1. common/
  2. darwin-x86_64/
  3. linux-x86_64/
  4. .gitignore
  5. Android.bp