Secondary migration from google3 into AOSP.

The 2nd revival of AOSP acloud is upon us!

The cl revision the acloud g3 code was pulled from is 195930083.

Things I did:
- Added AOSP copyright for new files and updated g3 imports to be relative.
- Merged in changes into existing files (easier to see changes here and
  for future cls).
- Scrubbed default.config of project and build info.
- Merge acloud.py (from g3) into acloud_main.py (entry point for AOSP
  acloud).
- Regenerated internal_config_pb2.py and user_config_pb2.py.
- Removed add_mock from gcomputer_client_test and added TODO in file
  where to replace it and updated parameterized to import from
  absl.testing.
- Updated references to gce_x86 to aosp_cf_x86_phone and updated branch
  references to 'aosp-master'.

Thing to note:
- New files fail pylint (in order to make it easy to check history on new files,
  formatting will be done using yapf in another cl).
- pip install acloud.zip seg faults so investigation and fix for that
  will happen in another cl.
- User needs to 'pip install absl-py' for parameterized lib in unittests.

Bug: 79684654
Test: ./run_tests.sh
Change-Id: I060641227d7c9162a45557e732686f22b83895e9
diff --git a/public/errors.py b/public/errors.py
index c027e40..0f4c644 100755
--- a/public/errors.py
+++ b/public/errors.py
@@ -16,8 +16,6 @@
 
 """Define errors that are raised by the driver."""
 
-import json
-
 HTTP_NOT_FOUND_CODE = 404
 
 
@@ -72,13 +70,17 @@
     """
 
 
-class DeviceBootTimeoutError(DriverError):
-    """Raised when an AVD defice failed to boot within timeout."""
-
-
 class HasRetriableRequestsError(DriverError):
     """Raised when some retriable requests fail in a batch execution."""
 
 
 class AuthentcationError(DriverError):
     """Raised when authentication fails."""
+
+
+class DeviceBootError(DriverError):
+  """To catch device boot errors."""
+
+
+class DeviceBootTimeoutError(DeviceBootError):
+  """Raised when an AVD defice failed to boot within timeout."""