A64: Hardwire the decoder and the simulator

If one of --trace-sim --debug-sim or --log-instruction-stats flags is
given, we use the decoder dispatcher instead.

BUG=none
R=rodolph.perfetta@arm.com, ulan@chromium.org
LOG=n

Review URL: https://codereview.chromium.org/177533023

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@19564 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Refactoring: Deprecate optparse in push and merge scripts.

- Deprecate optparse with argparse
- The tests include now options parsing by default: each test specifies the command-line args to parse rather than the options directly

This CL is split off from https://codereview.chromium.org/173983002/

TBR=ulan@chromium.org

Review URL: https://codereview.chromium.org/181583002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@19565 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Fix patch creation in merge-to-branch script.

Patch white space got stripped, which lead to failures when applying the patch.

- Refine test to reveal the problem
- Create a separate method for retrieving the patch that doesn't strip white space

R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/181603002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@19566 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Merge remote-tracking branch 'upstream/bleeding_edge' into bleeding_edge