Add "Home" directory support.

Update FilesActivityUiTests to verify Home is present
    and that clicking a root sets the title accordingly.
Guard addition of WRITABLE flag with a volume test.

Bug: 25147243
Change-Id: Ic20372737cae08a82af0aade0c0dbbd8c22d5f34
5 files changed
tree: 123fb0e4970e6805997387ac6930e38cbe24406c
  1. res/
  2. src/
  3. tests/
  4. Android.mk
  5. AndroidManifest.xml
  6. wrap_alpha.py